In a mixing bowl, combine all-purpose flour, baking powder, salt, and granulated sugar. Add room temperature butter and mix until you have a soft dough that holds together. Pour in vanilla extract and continue blending until fully incorporated.

Chill the dough in the refrigerator for at least 30 minutes. During this time, preheat your oven to 175°C (350°F). After chilling, scoop the dough and roll it into uniform balls.

Roll each dough ball generously in powdered sugar. Place them on a lined baking sheet, leaving space between each one. Bake in the preheated oven for about 12 minutes.

Remove the cookies from the oven and let cool for a minute. Gently press the back of a teaspoon into the center of each cookie.

Beat the softened mascarpone cheese in a bowl until smooth. Gradually add heavy cream and mix until glossy and thick.

Fill the crater in each cookie with the mascarpone mixture using a piping bag or spoon. Dust tops lightly with cocoa powder.

Serve immediately or chill briefly if needed.