Make the dough. Beat the butter and sugars until light in fluffy, then beat in the egg and vanilla. Add in the dry ingredients and beat to combine.
Chill the dough. Form the dough into a disk, cover tightly with plastic wrap, and refrigerate for at least an hour. Remove from the fridge 10 minutes before you plan to use it.
Form the cookies. Roll the dough into 1 inch balls. Use your thumb to make an indentation in the middle, making sure to not crack the cookie dough. Fill each cookie with 1/2 teaspoon of jam.
Chill. Freeze the cookie sheet of cookies for 10 to 15 minutes, until firm.
Bake. Bake for 10 to 11 minutes, until light golden brown. Let sit for 5 minutes, then transfer to a rack to cool completely. Dust with powdered sugar.
Tips for Success
Here are a few helpful tips to keep in mind when making these jam thumbprint cookies.
Make sure that your measurements are exact. Too much flour will cause the cookies to be dry and hard. Too little flour will cause the cookies to spread too much. We always recommended spooning the flour into your measuring cups and leveling off with a knife.
Ensure smooth cookies. Roll the cookie dough balls between your hands until they are really smooth and there are no lines or cracks in the dough. Gently press the centers with your thumb and make sure the dough does not crack. If the dough happens to crack, press the crack back together and smooth it out with your fingers.
Warm the jam. If your jam is too firm from being in the fridge, place it in a microwave-safe bowl and heat it in the microwave for just a few seconds, just until it is easy to stir (make sure it’s not too melted, just easy enough to stir).
Make sure you chill the dough before baking. This will prevent the cookies from spreading and you will get the pretty results as shown in the photos.
Proper Storage
Room temperature. Store thumbprint jam cookies in an airtight container at room temperature for up to 4 days. You may want to add parchment paper between layers to prevent the jam from sticking to other cookies.
Freeze. Freeze unfilled thumbprint cookies, layered between waxed paper, in freezer containers. When ready to use, thaw in covered containers and fill with preserves.
