I used to make my lemon bars with milk. One day I was out of it, so I substituted sour cream. What a difference! Richer custard with more tang. These have lots of lemon filling on a buttery shortbread crust.
1 cup (2 sticks) unsalted butter, at room temperature
3/4 cup granulated sugar
1 teaspoon vanilla extract
2 cups all-purpose flour
¾ teaspoon kosher salt
2 cups granulated sugar
¼ cup all-purpose flour
1 cup freshly squeezed lemon juice, from 4 large or 6 medium lemons
1 tablespoon finely chopped lemon zest
½ cup sour cream
½ teaspoon salt
Confectioners’ sugar for dusting
Preheat the oven to 350°. Line a 9 x 13-inch pan with foil, letting it extend over 2 ends. Spray the foil
To make the crust: In a mixing bowl, beat the butter and sugar on medium speed until light and fluffy, about 3 minutes. Add vanilla and mix to incorporate. Reduce speed to low and add the flour and salt, mixing until incorporated. The dough should be crumbly. This happens quickly; the mixture will look dry and then will combine into clumps. Don’t overmix or the crust will be difficult to distribute in the pan.
Transfer dough to prepared pan and use your fingers to evenly distribute it over the bottom. Then bring the dough up the sides of the pan slightly to contain the filling. Press the crust lightly. Bake for 20 to 25 minutes or until golden.
Make the filling: While the crust is baking, add the eggs to the mixing bowl (no need to wash it) and mix lightly. Add the sugar and flour and mix to combine. On low, mix in the lemon juice zest, sour cream and salt.
Lower the oven temperature to 325°. Whisk the filling to reblend it just before pouring it over the warm crust. Bake until the filling feels firm when touched lightly, about 20 minutes. Cool to room temperature.
Remove from pan by pulling up on foil. Remove foil and cut into 1 ½-inch to 2-inch squares.
MAKE AHEAD: Refrigerate for several days or freeze.
Serve chilled or at room temperature. Dust generously with confectioners’ sugar before serving.
Makes 24 squares.