Add the flour and baking powder to a mixing bowl and whisk together. Set aside

Add the sugar and butter to a separate mixing bowl. Use a hand-held mixer until it is light and fluffy. Add the milk and vanilla extract; beat well.

Stir the flour mixture into the sugar mixture until combined. Cover and refrigerate for 30 minutes, or until firm.

Preheat oven to 350 degrees F. Spray two cookie sheets with no-stick cooking spray.

Roll 15 balls out of the cookie dough. Use your thumb to press into the center of each ball. Do not press all the way through. Fill each center with jam.

Bake 12 minutes, or until the bottom of the cookies are golden. Let cookies sit on the cookie sheet 1-2 minutes, then transfer to a wire rack to cool.