Nutella Thumbprint Cookies

Instructions

1. Preheat the oven to 350°F. Line two baking sheets with parchment paper or silpat mats (or spray with nonstick spray).
2. In a medium bowl, whisk together the flour, sugar, cocoa and salt.
3. In a separate, larger bowl, use an electric mixer to beat the butter until it’s light and fluffy (about 2 minutes). Add the egg yolks and vanilla and beat well. Mix in the flour mixture at low speed, until just combined.
4. Turn the dough out onto a sheet of wax paper and knead a few times until it is smooth and shiny. Shape the dough into 24 (1-inch) balls. Arrange the balls 1-inch apart on the prepared baking sheets. Press your thumb into the center of each cookie, leaving an indentation.
5. Bake one cookie sheet at a time for 10 minutes. Remove the cookies from the pans and cool completely on wire racks.
6. Spoon a generous teaspoonful of Nutella into the center of each cooled cookie. It's best to store them in a single layer in a covered container.