Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper or a silicone baking mat.

In a large bowl, beat the softened butter and granulated sugar with an electric mixer until light and fluffy, then beat in the vanilla extract.

In a separate medium bowl, whisk together the flour, cocoa powder, and salt.

Gradually add the dry ingredients to the wet, mixing on low speed until a soft dough forms; do not overmix. Roll dough into 1-inch balls, place them on the baking sheet, and gently flatten each cookie.

Bake for 10-12 minutes until the edges are set, then cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.