These Lemon Gooey Bars get a triple dose of lemon, from lemon cake, lemon zest, and lemon curd. Moist, chewy, and amazing!See below the recipe card for step-by-step images.
Preheat oven to 350 degrees F. Line a 9x9 baking pan with parchment paper that has a slight overhang on 2 sides, then lightly spray with nonstick spray.
With an electric mixer, cream the butter until smooth and fluffy. Beat in the cake mix, egg, and lemon zest until combined and a thick dough forms.
Press 2/3 of the dough in the bottom of the prepared pan.
Spread the lemon curd evenly on top of the dough, leaving a 1/4 inch border around the edges bare.
Sprinkle the white chocolate chips over the lemon curd, then drizzle the sweetened condensed milk over the top of the chocolate (leave a little border bare, without sweetened condensed milk.)
Break up the remaining dough into 1/2 to 1 inches pieces and sprinkle it over the top of the bars (leave some of the sweetened condensed milk exposed so you have a cobbled look once baked.) Press down on the dough pieces lightly to seal.
Bake for about 29 to 32 minutes, until slightly browned.
Cool completely, then make sure to chill in the fridge for a few hours before cutting into 16 small bars.