Heat oven to 350F and line a 9x13 baking dish with parchment paper.

Whisk together 2 1/2 cups of flour with the powdered sugar and salt, then pour in the melted butter and mix until combined.

Sprinkle the dough into your lined pan and press down into a flat layer. Bake at 350F for about 20 minutes or until a light golden color.

While the crust is baking, add the sugar to a food processor with the lemon zest. Pulse until the zest is fully incorporated and sugar is a light yellow color.

Add the sugar and remaining half cup of flour to a large bowl and mix well.

Pour in the lemon juice and add the eggs, then mix very well until completely combined.

Pour the filling onto the warm crust, then transfer to the oven and bake for about 25 minutes, removing halfway to turn.

Remove from oven and allow to cool for an hour before chilling in the refrigerator for two hours.

Dust with powdered sugar and cut into bars using a clean, sharp, damp knife.