Poppy Seed-Lemon Bars

Preheat the oven to 350 degrees F (175 degrees C). Coat an 8-inch square baking dish with cooking spray.

Combine butter and confectioners' sugar in a bowl; beat with an electric mixer until creamy, 2 to 3 minutes. Add flour, salt, and cardamom; mix until just combined. Stir in poppy seeds until evenly distributed. Press dough evenly into the prepared baking dish with floured hands.

Bake crust in the preheated oven until edges are just starting to brown, about 18 minutes.

While the crust is baking, combine sugar, eggs, lemon juice, and lemon zest in a bowl. Beat with an electric mixer until smooth, 1 to 2 minutes. Add flour and stir until just combined.

As soon as the crust comes out of the oven, pour the filling into it and return to the oven.

Bake until filling is puffy and lightly browned around the edges, about 30 minutes. Place on a wire rack and cool completely before cutting into 16 squares. Dust lightly with confectioners sugar.