In a food processor, combine flour, sugar, and salt. Then pulse in the butter until dough forms.
Press the crust into an 8x8in baking pan that has been sprayed with cooking spray. Bake at 350°F for 15-20 minutes. Remove from the oven and allow to cool.
In a mixing bowl, combine eggs, sugar, lemon juice, and lemon zest. Then add in flour, mixing until combined. Pour the lemon filling over the crust.
Bake at 350°F for 20-25 minutes, the center will be a little jiggly. Allow to cool and then refrigerate for a minimum of 2 hours. Before serving dust with powdered sugar.