Preheat oven to 350°F.

Combine brown sugar, butter, vanilla extract, and egg yolks in a medium bowl.

Using a mixer, or your utensil, mix the ingredients until smooth.

Add flour and salt to the mixture gradually. Sifting the dry ingredients into the wet batter may help. Be sure you mix in between each addition!

Once the mixture has a doughy texture shape the cookie batter into small one inch balls. After the balls are on the pan push a hole into each ball, if using your finger place finger in flour first to make a clean hole, and to avoid a mess! Then add your jelly or jam and place in the holes.

Bake for 20 minutes, or until light brown