01 - Preheat oven to 350°F and line a baking sheet with parchment paper
02 - Beat softened butter and granulated sugar in a large bowl until mixture becomes light and fluffy
03 - Mix in egg yolk and vanilla extract until fully incorporated
04 - Gradually blend in flour and salt, mixing just until dough comes together
05 - Roll dough into 1-inch balls and arrange on prepared baking sheet, leaving 2 inches of space between each
06 - Press a deep well into the center of each dough ball using your thumb or the back of a spoon
07 - Spoon approximately 1/2 teaspoon of lemon curd into each indentation
08 - Bake for 10 to 12 minutes until edges begin to turn golden brown
09 - Let cookies rest on baking sheet for 5 minutes, then transfer to wire rack to cool completely. Dust with powdered sugar before serving if desired