Looking for a super easy, delicious but also impressive dessert? How about Gluten Free Key Lime Pie Bars. A buttery gluten-free shortbread crust, creamy key lime pie filling topped with a dollop of homemade whipped cream and lime sugar. You will not believe how easy they are to make. This luscious dessert is perfect for get-togethers and pot lucks. Definitely a crowd pleaser.
If you love citrus recipes, make sure to check out my Gluten Free Lemon Curd Linzer Cookies and my Gluten-Free Lemon Bars

Jump to:
- Recipe Ingredient Notes
- Tools needed to make Gluten Free Key Lime Pie Bars
- How to make Gluten Free Shortbread Crust
- How to make Gluten Free Key Lime Pie Bars
- How to slice key lime bars
- How to decorate and serve Key Lime Pie Bars
- Frequently Asked Questions about Key Lime Bars
- Baking in grams
- Note about Ovens and Oven Temperatures
- Substitutions and Modifications
- 📖 Recipe
- 💬 Comments
Recipe Ingredient Notes
Gluten Free Flour: For the shortbread crust I use my own gluten free flour blend. This recipe works great with Bob’s Red Mill 1 to 1, King Arthur Measure for Measure or Cup4Cup, or any gluten free flour blend you may have on your hands. The shortbread crust is very forgiving.
Condensed Milk: Condensed milk is a form of cow’s milk that has had the majority of the water removed, leaving behind a thick, milk paste. Condensed milk is sweetened. Make sure not to buy evaporated milk by accident (If you are located in Austria/Germany please look for "Gezuckerte Kondensmilch")
Key Limes: Finding key limes at the store can be a hit or miss. So if you can't locate key limes, I recommend using regular limes, also known as Persian limes. They are easier to juice anyways and just as good. I am not a fan of bottled lime juice. While some people swear by it, it tastes artificial to me.
Sour Cream: The sour cream helps to balance out the sweetness from the condensed milk. I use full-fat sour cream. If you don't have sour cream on hand, please substitute it with a full-fat yogurt such as Greek yogurt.
Egg Yolks: The added egg yolks make the key lime pie filling smooth and creamy.
Heavy Cream: For garnish, I use fresh whipped cream made with heavy cream. Of course, you can use premade whipped cream or cool whip.

Tools needed to make Gluten Free Key Lime Pie Bars
To make key lime pie bars, I recommend the following tools
- a 8x8 or 9x9 baking pan (if you use a 9x9 pan, the bars will be thinner)
- parchment paper to line the baking pan with
- a juicer and zester for the limes (the fine side of a box grater works for the zest too)
- a medium sized plastic or glass bowl to make the filling in. try to avoid a metal bowl if possible
- a whisk, a flexible spatula and a small offset knife
- can opener
- mixer to make whipped cream with for garnish (you may also whip this by hand with a whisk)
How to make Gluten Free Shortbread Crust
Traditionally key lime pies and key lime bars are made with a graham cracker crust. Since gluten free graham crackers can be expensive, I opted for a simple shortbread crust instead.
- Preheat the oven to 350F and arrange your baking rack in the middle. This is the perfect spot for your baked goods to bake evenly.
- Line an 8×8 (or 9×9 pan) with parchment paper and set aside. Make sure to leave some overhang on the sides to remove the gluten free key lime bars easily from the pan.
- Whisk together the gluten free flour, brown sugar and salt in a medium sized bowl. Cut your butter in small pieces and add to the flour mixture. You can use your clean hands or two forks to work the butter into the flour until it is crumbly.
- Press the mixture in an even layer into the prepared pan. I like to use an offset knife for this or the back of a spoon.
- Bake the crust at 350F for 12 to 14 minutes or until light golden brown.
- Remove your key lime pie crust from the oven, make sure to leave the oven on.
How to make Gluten Free Key Lime Pie Bars
Making the filling for key lime pie bars is no rocket science. If you can use a can opener, you can make key lime pie bars. I am serious.
Zest two limes and set aside. Juice the limes and strain out any seeds. In a large bowl combine the condensed milk, sour cream, egg yolks, and freshly juiced lime juice and whisk together until smooth. Stir in the lime zest.
Pour the filling on top of the parbaked shortbread crust and with a small offset knife or the back of a spoon smooth out evenly.
Bake at 350F for 18-20 minutes. The filling should be almost all the way set and should not turn brown. Remove the key lime bars from the oven and allow for them to cool to room temperature before transferring them to the fridge. I recommend allowing the bars to chill for at least 3hrs before cutting them.
You can make Gluten-Free Key Lime bars up to 3 days ahead of time and can even freeze them if needed (major bonus for the holidays) Just skip the toppings until you are ready to serve.

How to slice key lime bars
Cold, very well-set key lime bars are easier to cut than a warm ones. Always use a long, very sharp, knife, preferably thin. I also like to use a pitcher with hot water instead of running hot water constantly while cutting.
What you will need to slice picture-perfect key lime bars
- cold, well set key lime bars
- a pitcher with HOT water
- clean, dry towel
- sharp Chef’s Knife
Dip your Chef’s Knife in the hot water and dry very well with the towel. The hot water will warm up the blade and will slide through the key lime bars a lot easier.
Clean your knife in between cuts in the hot water, wipe clean, and continue cutting. The cleaning is the very important part here. If you skip this step your gonna smudge all the leftovers from your previous cut onto the next cut.
How to decorate and serve Key Lime Pie Bars
I topped my gluten free key lime pie bars with sweetened whipped cream (also known as Crème Chantilly). As a garnish, I kept it simple and used some lime sugar and a slice of fresh lime. To make lime sugar, combine some lime zest and granulated white sugar in a small bowl and rub the zest into the sugar. Allow for it to sit at room temperature for it to dry out a bit.

Frequently Asked Questions about Key Lime Bars
Can I use regular limes instead of key limes?
Finding key limes can be hit or miss. There is nothing wrong with using regular limes (persian limes) in this recipe.
Can I use bottled lime juice?
If you can't locate fresh key limes, I recommend using regular limes instead. Personally, I am not a fan of bottled lime or lemon juice.
Do key lime bars need to be refrigerated?
Yes, key lime bars need to be refrigerated after baking so they can be set up fully. If you plan on serving them at a “buffet style” gathering, I only recommend having them at room temperature for up to 2hrs.
How far in advance can I make key lime bars?
Gluten Free Key Lime Pie Bars can be made up to 3 days ahead of time. Just wait to garnish them until you are ready to serve them.
Can you freeze key lime bars?
Yes, key lime bars can be frozen. I highly recommend freezing them without any garnishes. Just like freezing cookie dough, I recommend freezing the slices individually on a sheet tray (uncovered) first before transferring them to an airtight container. You may also freeze the entire uncut pan of key lime bars. To freeze the entire pan I recommend placing it on a sheet tray and place in the freezer until fully frozen. Once frozen wrap in plastic wrap and aluminum foil (or if you have a big enough ziplock bag). Freeze for up to 2 months. When ready to eat allow for it to thaw in the refrigerator.
I don’t have celiac. Can I make this recipe?
Yes. Please use 135g of regular flour for the shortbread crust.
I can't tolerate eggs - can I make this recipe?
Good News - this recipe can be made without the egg yolks. No need to substitute them with another ingredient. Just reduce the baking time to 15 minutes.

Baking in grams
I share my recipes in grams and by weight since baking by weight is the most accurate way to bake. Digital Scales are very affordable and very affordable. You can purchase them on Amazon for less than a set of measuring cups. Measuring cups are very inaccurate and can cause significant errors when it comes to gluten-free baking or baking in general. Especially since I bake with gluten-free flours which weigh differently than “regular” flours. I do provide some ingredients like spices and leavening agents in measuring spoons. To learn more about Baking with a digital scale, make sure to check out my post about Baking by weight.
Note about Ovens and Oven Temperatures
All my recipes are tested and developed with a conventional oven. I always bake my baked goods on the rack placed in the MIDDLE of my oven. This way the heat coming from the bottom will not burn my baked goods.
If you are baking with convection (fan-forced), please adjust the recipes accordingly. Be also prepared that the convection oven can cause your baked goods to dry out quickly and still be raw inside. Be aware that it takes at least 15-20 minutes for a standard American Oven to be fully preheated. I highly recommend investing in an Oven Thermometer.
Substitutions and Modifications
Any dietary or ingredient modifications/substitutions to this recipe may alter the end result in appearance and taste. I test my recipes several times as published in this post and The Gluten Free Austrian Blog is not responsible for the outcome of any recipe you find on our website.

📖 Recipe
Gluten Free Key Lime Pie Bars

Looking for a super easy, delicious but also impressive dessert? How about Gluten Free Key Lime Pie Bars. A buttery gluten-free shortbread crust, creamy key lime pie filling topped with a dollop of homemade whipped cream and lime sugar. You will not believe how easy they are to make. This luscious dessert is perfect for get-togethers and pot lucks. Definitely a crowd-pleaser.
Ingredients
For the Gluten Free Shortbread Crust
- 150 grams gluten free multipurpose flour
- 50 grams light brown sugar
- ½ teaspoon ground cinnamon
- ½ teaspoon (2 gram) kosher salt
- 85 gram unsalted butter, cold
For the Key Lime Bars
- Two 14-oz cans sweetened condensed milk (798 grams)
- 165 grams fresh squeezed lime juice
- 120 grams full fat sour cream
- 2 large egg yolk, at room temperature
- 1-2 teaspoons of lime zest
Sweetened Whipped Cream
- 235 ml heavy whipping cream, cold
- 40 grams powdered sugar
- 1 teaspoon vanilla extract
Lime Sugar
- 50 grams granulated sugar
- zest of one lime
- Additional Lime for Garnish
Instructions
How to make Gluten Free Shortbread Crust
- Preheat the oven to 350F
- Line an 8×8 (or 9×9 pan) with parchment paper and set aside. Make sure to leave some overhang on the sides to remove the cheesecake easily from the pan.
- Whisk together the gluten-free flour, brown sugar, cinnamon, and salt in a medium-sized bowl.
- Cut your butter into small pieces and add to the flour mixture. You can use your clean hands or two forks to work the butter into the flour until it is crumbly.
- Press the mixture in an even layer into the prepared pan. I like to use an offset knife for this or the back of a spoon.
- Bake the crust at 350F for 12 to 14 minutes or until light golden brown.
- When your crust is done baking, do NOT turn off the oven.
How to make Gluten Free Key Lime Pie Bars
- Zest two limes and set aside. Juice the limes and strain out any seeds.
- In a large bowl combine the condensed milk, sour cream, egg yolks, and freshly juiced lime juice and whisk together until smooth. Stir in the lime zest.
- Pour the filling on top of the parbaked shortbread crust and with a small offset knife or the back of a spoon smooth out evenly.
- Bake at 350F for 18-20 minutes. The filling should be almost all the way set and should not turn brown.
- Remove the key lime bars from the oven and allow for them to cool to room temperature before transferring them to the fridge. I recommend allowing the bars to chill for at least 3hrs before cutting them.
How to make Sweetened Whip Cream
- Add the heavy cream, powdered sugar, and vanilla to the bowl of your stand mixer fitted with the whisk/balloon attachment. Whisk at a medium speed until medium-stiff peaks have formed.
- Transfer the whipped cream to a piping bag fitted with a star tip and garnish the gluten free key lime bars when ready to serve.
- Finish the key lime bars with some lime sugar and thinly sliced limes.
How to make Lime Sugar
- To make lime sugar, combine some lime zest and granulated white sugar in a small bowl and rub the zest into the sugar.
Nutrition Information:
Yield:
8Serving Size:
1Amount Per Serving: Calories: 250
Calories are a guestimate.
Kelli says
I can’t wait to make these. I’ve never made a lime sugar garnish before - this sounds like a perfect pairing with the bars and Chantilly crème!
Daniela says
Lime sugar or citrus sugar (you can use any citrus you would like) is a fun and easy garnish. You could even use it to make shortbread cookies. Rubbing the zest into the sugar makes it really flavorful.
Jennifer Sutherland says
I am going to have to make these. Key Lime Pie was one of the few pastries my mom would ever make, and it's such a fond memory of childhood. Thank you!
Daniela says
I hope you will love them. It's a super simple recipe but really hits the spot
Kelly says
Looking forward to making this for Easter! About how any Persian limes will I need?
Thank you.
Daniela says
Kelly, this is a tricky question. The limes at my local Hispanic market are medium sized and I think I used 8?
Kelly says
I made these bars for Easter and oh my they were amazing! Everyone loved them. The crust was delicious with the hint of cinnamon and the filling was perfect. I found the recipe very easy to make even though it was the the first time I’ve baked a recipe using weighed ingredients . I will definitely be making these again and can’t wait to try more of your recipes!
Daniela says
I am so proud of you for using a scale <3
Jules says
Hi there and thank you for this! The filling tastes incredible! I have one question regarding cooking time! My oven has been on for over an hour at 350 (oven thermometer confirmed) . I placed in my bake and set the timer for 20 min (looking through the window and checking periodically). I just went to take it out and it’s not even close to set, so I’m leaving it in a bit longer! The filling was so creamy and lovely…there was just a lot of it given the 2, 14oz cans, so I didn’t even fill the 9x9 and kept some out for smaller cups, so I thought it might cook even faster. Your instructions are so detailed, and it’s a very easy recipe, so I’m not sure where I might be going wrong with the cooking time. Any thoughts?
Thank you so much!!
Daniela says
Hello, I am slightly confused here. The bars only bake for around 20 minutes, until the filling is almost set. It will still be jiggly in the middle and finish setting up in the fridge. Did you make any ingredient substitutions? And did you use condensed milk (and did not use evaporated milk)?
jules says
Thank you for your quick reply! And my sincere apology. I always use sweetened condensed oat milk due to a lactose issue, so that must be my downfall. I’m going to try and make smaller batches now to see if that will render a better bake. It’s just so delicious and I’ve had such a hard time finding something this good! I appreciate your time and amazing recipes!
Daniela says
Yes, this recipe will not work with a product like sweetened condensed OAT milk. This is the reason your filling is too thin and will not set up in the oven. You need a lot more egg yolks, reduce the amount of condensed OAT milk and add some sort of starch as a binder. In the end a totally different recipe than my recipe for Gluten Free Key Lime Pie Bars.
Kara says
These bars were amazing and super easy to make!! Daniela, have you ever tried substituting the regular sweetened condensed milk with the fat free one? Just curious if it worked out.
Thanks for all you do for the gf community!
Daniela says
Hi Kara, I actually have never even purchased fat-free condensed milk. I would be worried that the key lime bars lose their creaminess.
TIFFANY says
Hi if I opt for graham cracker , what are the measurements to make the crust?
Daniela says
I haven't made a graham cracker crust in forever but this is what I used last time:
160 g graham cracker crumbs
50 g unsalted butter, melted
50 g white or light brown sugar
⅛ teaspoon salt
Jackie Jeffries says
These are the best! Have made them twice and every one loves them.. Never guess they are gluten free. Keeps well in the frig if you have leftovers.