Preheat the oven to 350 degrees.
Line an 8 X 8 inch baking pan with parchment paper.
Mix the flour, powdered sugar, and butter together until a soft dough forms.
Press this dough evenly in the bottom of the baking pan.
Bake at 350 degrees for 20 minutes.
Add the zest, juice, sugar, flour, salt, and eggs into a blender/food processor.
Pulse until light and frothy.
When ready, remove the crust from the oven.
Pulse the mixture one more time.
Pour the filling on the top of the hot crust.
Return to the oven and bake at 350 degrees for 25 minutes.
Remove from the oven when done and set aside and cool completely to room temperature.
Just prior to serving sprinkle powdered sugar on top.