Preheat your oven to 350°F (175°C).
Line your baking sheet with parchment paper.
In a large mixing bowl, cream together the softened butter, light brown sugar, and granulated sugar until light and fluffy.
Beat in the eggs one at a time, followed by the vanilla extract.
In another bowl, whisk together the flour, cocoa powder, baking soda, baking powder, and salt. Gradually add to the wet mixture, mixing until just combined.
Cover the dough with plastic wrap and refrigerate for about 30 minutes.
Use a cookie scoop to portion out the dough, roll each scoop into a ball, and roll it in granulated sugar.
Flatten half of each dough ball slightly, place about a tablespoon of chilled hot fudge in the center, and cover with the other half, pinching to seal.
Place the filled dough balls on the prepared baking sheet, leaving space between each cookie. Bake for 10-12 minutes.
Cool on the baking sheet for 5 minutes before transferring to a cooling rack.