In a bowl of a electric mixer, beat the butter and sugar until light and fluffy. Add the egg yolk and vanilla extract and beat until combined.
2
In a separate bowl, whisk together flour,baking powder and salt. Add the flour mixture to the batter and beat just until combined. Refrigerate for about 30 to 60 minutes if the batter is too soft to roll.
3
Preheat the oven to 350 degrees.
4
Roll the dough and using your thumb or end of a wooden spoon, make a indentation into the center of each cookie and fill with about 1/2 teaspoon of jam.
5
Bake for about 12-15 minutes, or until cookies are set.
