Preheat oven to 350 F. Line an 8x8 baking dish with parchment paper.
In a food processor or blender, combine the coconut oil or ghee, egg, baking soda, and coconut sugar. Blend for 20-30 seconds until thoroughly mixed. (You can also use a whisk or your hand for this step)
Add in almond flour and blend until a dough forms. Allow dough to rest in the freezer for about 5 minutes.
Using your hands or a spatula, place dough in the parchment paper-lined 8x8 baking dish and cover the entire bottom of the pan with the dough evenly spread.
Bake at 350 F for 15 min.
Lemon Bar Filling
Prepare the lemon filling by combining eggs, lemon zest, lemon juice, maple syrup, tapioca flour, and coconut flour in a bowl and mix well.
Remove the shortbread crust from the oven once done, then reduce the oven to 325 F.
Pour lemon filling over the shortbread crust and bake in a 325 F oven for 18 - 20 minutes.
Remove from oven, let cool, then refrigerate for at least 2 hours before cutting.
Sprinkle with powdered sugar* if desired. Enjoy!
Notes
Add the lemon filling to the shortbread crust while the crust is still warm.
I recommend using an oven thermometer to avoid the lemon filling crack too much due to the higher temperature.