Preheat the oven to 350°F (175°C) and line baking sheets with parchment paper.

In a large mixing bowl, cream the softened unsalted butter and granulated sugar until light and fluffy, about 2-3 minutes.

Add in the eggs and vanilla extract, mixing until well combined.

Gradually add the all-purpose flour, mixing until just combined, being careful not to overmix.

Shape the dough into 1-inch balls and place them on the prepared baking sheet, spacing them 2 inches apart.

Press down in the center of each dough ball to form a deep thumbprint.

Bake for 10-12 minutes until edges are lightly golden and tops are set.

Cool for 5 minutes on the baking sheet before transferring to a wire rack to cool completely. Fill the thumbprints with icing or toppings.