In a large bowl, beat the softened butter and powdered sugar until light and fluffy.

Mix in the vanilla extract, salt, and cocoa powder until smooth.

Gradually add the flour on low speed until the dough comes together.

Gently fold in chocolate chips and nuts, if using.

Roll the dough into small, even balls using your palms.

Bake at 350°F (175°C) for 8–12 minutes, until the cookies look set and matte.

Cool completely, then roll in powdered sugar before serving.