Add the flour, butter, and powdered sugar to a bowl and beat with a mixer until the dough comes together. See notes.
Press the dough into an ungreased 8x8 baking dish.
Bake for 20 minutes.
For the filling
Add the eggs, sugar, flour, baking powder, lemon juice, and lemon zest to a mixing bowl and whisk until well combined.
Pour the filling over the crust and return to the oven for 25 minutes. The filling should be just slightly jiggly.
Cool for one hour before dusting with powdered sugar.
Video
Notes
Depending on the brand and quality of butter that you use, the dough may not come together no matter how long you mix it. If it does form a soft ball, go ahead and press that into the pan as directed using your hands. If you're left with a sandy, coarse mixture just go ahead and dump that in the prepared pan and use a clean drinking glass to press the mixture together to form the crust. This will bake up just the same - the end result will be a buttery crust that holds together well.Store lemon bars tightly covered in the refrigerator for up to 4 days.Recipe from a Taste of Home magazine.