Preheat your oven to 350 degrees. 

Grease an 8×8” glass baking pan or line it with parchment paper. (Parchment paper makes it easy to remove and cut your lemon bars, however greasing the pan works too.)

For the shortbread layer, mix the melted butter and 1/3 cup sugar together, then mix in the 1 1/4 cup gluten-free flour. Press into the baking pan. I use my clean fingers to press it in but you can use a spoon if you prefer. Bake for 18-22 minutes or until the edges are just beginning to turn golden brown. Remove from the oven and set aside. 

For the lemon filling: While the shortbread layer is baking, you can make the lemon filling. Using a whisk or whisk attachment on your stand mixer, beat the eggs, then add 1 cup sugar, baking powder, and ¼ cup flour. Scrape the sides and mix well. Turn the mixer to high and slowly add the lemon juice to the egg mixture. Mix on high speed until it begins to look frothy. 

Reduce the oven temperature to 325 degrees. Pour the lemon filling over the just-baked shortbread layer. (Note: if you get busy and the shortbread layer begins to cool, don’t worry – just bake the bars a little longer.) 

Bake for 22-28 minutes or until the top is just turning golden brown and the center is set. Tap the pan gently with an oven mitt to test. If it jiggles, bake for a couple more minutes. If it doesn’t, your lemon bars are done.* 

These lemon bars will turn brown quickly if overbaked or the oven temperature is too hot, so pay close attention to the final minutes. If your lemon bars do turn brown on the top, they will still taste good; they just won’t look quite as pretty. 

Remove from the oven and set aside on a wire rack to cool completely. Once cool, use a sifter to dust a little powdered sugar over the top of the bars. (This also helps to cover up imperfections.)

*Poking the bars with a fork or toothpick to test for doneness is not recommended for this recipe as the filling needs time outside of the oven to set (firm) completely. If you wait until the bars test done with a fork, they will be overbaked.