Gluten Free Lemon Bars with Almond Shortbread Crust

When life gives you lemons, it's time to make some gluten-free lemon bars. A gluten-free almond shortbread crust topped with a thick, luscious layer of lemon custard and dusted with powdered sugar. They are bright, tart and buttery. And Gluten Free Lemon Squares are so easy to make.

Lemon Bars always remind me of summer potlucks and BBQs - they are the perfect make-ahead dessert everyone loves. The sturdy almond shortbread crust makes them easy to pick up and no one really needs utensils to enjoy them. This recipe makes an 8" rectangular square and depending on how big or little you cut them you will get 8-16 pieces from one pan.

If this is your first time making gluten free lemon squares, make sure to read the instructions before starting working on this recipe.

Are you a lemon lover? Make sure to check out my other lemon desserts like my Gluten-Free Lemon Curd Linzer Cookies and my Lemon Eclairs.

Recipe Ingredients 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 Gluten Free Flour, 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. The flour blends mentioned do contain xanthan gum.

Almond Flour: The almond flour gives the shortbread crust a nutty flavor which pairs very well with the tangy lemon curd. If you prefer to keep this recipe nut-free, please substitute the almond flour with the same amount of gluten-free flour. 

Butter: Please use unsalted, room temperature butter for the recipe (for the lemon curd and the shortbread crust). It should be around 65F which is a lot colder than many of us consider room temperature. To test if your butter is at room temperature nudge it with your finger. You should see an indent but the butter should not feel like you can poke right through it. 

Eggs: While many lemon bars are made with only egg yolks, I feel like it makes them taste eggy. This is why I use whole eggs and egg yolk in this recipe. Make sure to save the leftover egg whites. You can use them to whip up a batch of Marshmallows

Lemons: Personally, I am not a fan of bottled lemon juice and recommend using fresh lemons. If you can, I recommend using organic lemons in this recipe for Gluten-Free Lemon Squares. Especially when using their zest. No matter what, make sure to give them a good rinse.

Heavy Cream: The added heavy cream to the lemon curd filling gives it an extra creamy, luscious texture. If you are dairy-free, you could replace it with coconut cream.

Equipment Recommendation for Lemon Squares

To make Gluten Free Lemon Bars you will need the following equipment.

• a rectangular 8-inch baking pan
• Zester and a juicer – because we will need fresh lemon juice
• a nonreactive bowl (like a glass bowl or stainless steel)
• Heavy, non-reactive saucepan such as stainless steel, anodized aluminum, and enamel. I do not recommend using plain aluminum or unlined copper since those materials will react with the acid in the lemons. This will not only cause a discoloration but also a metallic taste.
• Whisk and a heatproof spatula
• fine mesh strainer and a bowl to strain your curd into

Gluten Free Almond Crust for Lemon Bars

Timing is everything when it comes to making Lemon Bars. Make sure to have all your ingredients measured out (for this amazing shortbread crust and the lemon curd).

Step 1: Heat the oven to 350F and arrange the baking rack in the oven in the middle. This is the perfect spot for your baked goods to bake evenly.

Step 2: Line an 8×8 with parchment paper and set it aside. Make sure to leave some overhang on the sides to remove the gluten-free lemon bars easily from the pan when they are fully cooled.

Step 3: Whisk together the gluten-free flour, almond flour, powdered sugar, 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.

Step 4: Press the mixture in an even layer into the bottom of the prepared baking dish. I like to use an offset knife for this or the back of a spoon. Make sure to get the edges of the pan.

Step 5: Bake the crust at 350F for 16 to 18 minutes or until golden brown. While the gluten-free shortbread crust is in the oven, make the Lemon Curd Filling

Remove your gluten free buttery shortbread crust from the oven, make sure to leave the oven on.

How to make Lemon Curd Filling and bake Lemon Bars

I have tested a few ways to make this lemon curd filling and pre-cooking on the stove is the perfect way to make them. Cooking the filling on the stove not only gives gluten-free lemon bars the best texture but also reduces the risk of the edges of the bars overbaking while the center is still raw.

Step 1: In a nonreactive bowl combine the granulated sugar, room temperature eggs, egg yolks, and salt and whisk together. Don't over whisk the eggs - they should NOT be frothy.

Step 2: Add your fresh squeezed lemon juice and whisk together. Transfer the mixture to the non-reactive saucepan and place the pot on the stove over medium heat.

Step 3: Whisk in the butter and lemon zest. Stir constantly, until the curd thickens considerably, 5 to 10 minutes. Do not allow for it to come to a boil. The lemon curd is ready when it leaves a path on the back of a spoon.

Step 4: Pour the cooked lemon mixture through a fine strainer set over a clean non-reactive bowl. This will remove any accidentally cooked bits and pieces of cooked eggs. Add the heavy cream to the curd and stir until fully incorporated.

Step 5: Once your lemon filling is strained, pour the lemon filling over the still-warm gluten-free almond shortbread crust. With the back of a spoon or a small offset knife, smooth out the filling and place it in the oven.

Step 6: Bake for 13-15 minutes, until the filling is shiny and the center portion of the lemon bars wiggles like firm jello when you lightly tap the edges of the baking dish. Like Lemon Curd, lemon bars will firm up while cooling. It is normal for the sides of the lemon curd to bubble while baking.

Step 7: Remove the gluten-free lemon squares from the oven and cool completely on a wire rack. Transfer them to the refrigerator for 2-3 hours (or overnight) before serving.

Step 8: When ready to serve, remove the lemon bars from the baking pan using the parchment as handles. Cut the lemon bars with a sharp, clean knife into squares or bars. Right before serving dust with powdered sugar.

How to store Gluten Free Lemon Bars

Gluten-Free Lemon Bars can be kept at room temperature for up to 4hrs but should be stored in an airtight container in the refrigerator for up to one week. This makes them a perfect make-ahead dessert option. You may also freeze leftover bars for up to 3 months in an airtight container (they taste deliciously frozen, especially on a hot summer day). Allow for them to thaw in the refrigerator.

Why do Gluten Free Lemon Bars have a white crust on top?

Sometimes lemon bars end up with a white, kinda bubbly-looking top. This happens when the eggs where over whisked while combining them with the sugar. Good News: if this happens to your batch of gluten-free lemon squares, it happens to the best of us. Just top the creamy lemon filling with some powdered sugar and enjoy them.

FAQ for Lemon Bars

How to cut gluten-free lemon bars
To cut the lemon bars, make sure they are well-set and cold. Use a long, very sharp, knife, preferably thin and dip it in a pitcher filled with hot water. Make sure to dry the knife with a clean towel. The hot water will warm up the blade and will slide through the lemon bars a lot easier. Clean your knife in between cuts in the hot water, wipe clean, and continue cutting.

Can I make this recipe with all-purpose flour?
To make this recipe for gluten-free lemon bars with all-purpose flour, please use 90 grams of AP in the gluten-free almond shortbread crust.

I overcooked my lemon filling - can I save it?
The overcooked lemon curd will be lumpy instead of smooth. If you happened to overcook the lemon filling, you can try to save it by blending it or smoothing it out with a stick-blender. The overcooked lemon curd will look like scrambled eggs. Make sure to cook your lemon curd at a low temperature and whisk continuously.

Can I make lemon squares with different citrus?
Technically you can but let's be honest, nothing will taste as good as traditional lemon bars. If you are in the mood for limes, I recommend checking out my Key Lime Bars.