Ingredients:

  • 1 cup unsalted butter, softened
  • 0.5 cup granulated sugar
  • 1 large egg yolk, room temperature
  • 1 teaspoon pure vanilla extract
  • 2.25 cups all-purpose flour
  • 0.25 teaspoon salt
  • 0.33 cup fruit preserves or jam

Instructions:

  1. Cream the Base: In a large bowl, beat the softened butter and granulated sugar together until the mixture is pale and fluffy (about 2–3 minutes).
  2. Incorporate Wet Ingredients: Add the egg yolk and vanilla extract. Beat on medium speed until fully combined and smooth.
  3. Add Dry Ingredients: Gradually stir in the flour and salt. Mix on low speed just until the flour streaks disappear.
  4. Shape the Dough: Scoop about 1 tablespoon of dough and roll it into a smooth 1-inch ball. Place balls 2 inches apart on prepared baking sheets.
  5. Create the Thumbprint: Use your thumb or the back of a rounded measuring spoon to gently press an indentation into the center of each ball.
  6. Fill and Bake: Fill each indentation with about 0.5 teaspoon of jam. Bake at 350°F (175°C) for 12–15 minutes until edges are set.
  7. Cool and Finish: Let the cookies rest on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.