Lemon Bars with Shortbread Crust

INGREDIENTS

1/2 cup

(1 stick, 113 g) unsalted butter, room temperature, plus more for pan

1/2 cup

confectioners' sugar, plus more for dusting

1/4 tsp

salt

1 cup

all-purpose flour, (spooned and leveled)

large egg yolks

1 can

(14 ounces, 396 g) sweetened condensed milk

Zest of 2 lemons

3/4 cup

fresh lemon juice (from about 3 lemons)