Grease the 8x8 pan with butter and cooking spray, or line with parchment paper. Set pan aside.
Make the Crust
In a medium-sized bowl, combine the flour, powdered sugar, salt, and lemon zest.
Add the butter. Cut the butter in with a pastry cutter or a fork until a little crumbly. Press the mixture evenly into the bottom of the greased pan.
Place the baking dish into the oven and bake for 15 minutes or until firm.
Remove from oven and allow to cool slightly.
Make the Custard
In a medium-sized bowl, whisk the eggs, sugar, baking powder, lemon juice, and flour until combined.
Pour the custard onto the baked crust.
Place the pan into the oven. Bake for about 30 minutes or until just set.
Remove pan from oven and let cool for 30 minutes.
Once cooled, place the pan in the refrigerator. Allow to chill for 2 hours or overnight.
Before serving, dust with powdered sugar or add a dollop on our Grammy's Cream Cheese Frosting and top sprinkle with lemon zest.
Notes
Culinarian Tips, Tricks, and Suggestions:Covering the pan with parchment paper makes for easy removal from the pan. Simply lift the parchment paper and place it on a cutting board. Cut the bars to the serving size you prefer.The way to tell if the custard is set is when it does not jiggle more than a little bit in the center.To keep the custard from sticking to the knife when cutting, run the blade under warm water and keep the blade clean between cuts.Try key lime juice and zest to add a little zing to this summer pastry.