01 -
Fire up your oven to 350°F. Grab an 8x8-inch baking dish and give it a light coating of butter. Line the whole thing with parchment paper, making sure you've got some paper hanging over at least two edges - this makes lifting out your finished bars super easy later on.
02 -
Grab a big mixing bowl and whisk your flour, powdered sugar, and salt together until they're well combined. Pour in your melted butter along with the vanilla extract, then grab a spatula and mix everything until it comes together into a greasy, crumbly dough. Dump this mixture into your prepared pan and use your hands to press it down evenly across the bottom, pushing it slightly up the sides about ⅛-inch.
03 -
Slide your pan into the oven and bake for 18 to 20 minutes - you're looking for edges that turn a nice light golden brown. Pull it out when it's done and poke holes all over the surface with a fork to prevent bubbling.
04 -
While your crust is baking, get started on the filling. Put your granulated sugar in a large bowl. If you're using lemon zest for extra flavor, toss it in with the sugar and rub it between your fingers - this releases all those amazing citrus oils into the sugar.
05 -
Add your flour to the sugar mixture and whisk until combined. Crack in your eggs and whisk them in thoroughly, then pour in the fresh lemon juice and whisk everything until you have a smooth, sunny yellow mixture.
06 -
Pour your lemon mixture right over the hot baked crust and return the pan to the oven. Bake for 20 to 25 minutes until the filling is completely set - give the pan a gentle shake and the center shouldn't jiggle anymore when it's ready.
07 -
Take your pan out of the oven and let it sit on the counter for a full hour to cool to room temperature. Once it's cooled down, pop the whole thing in your refrigerator and let it chill for another 2 hours until it's completely firm.
08 -
Once your lemon bars are thoroughly chilled, give them a generous dusting of powdered sugar on top. Use the parchment paper overhang to lift the whole slab out of the pan, then slice into 16 squares and enjoy!