Prepare Dough: In a bowl, whisk together all-purpose flour, baking powder, and sugar. In a separate bowl, combine the egg and milk, then mix these wet ingredients into the dry until a soft dough forms.

Make the Filling: In a mixing bowl, beat together the softened butter, powdered sugar, and vanilla extract until it’s creamy and well combined. Set this mixture aside.

Assemble Rolls: Roll out the dough on a floured surface into a rectangle. Evenly spread the creamy filling across the surface, then tightly roll the dough into a log shape.

Slice and Bake: Cut the rolled dough into equal pieces and arrange them on a baking sheet. Bake in a preheated oven at 350°F (175°C) for 15-20 minutes, or until golden brown and crispy.

Cool and Serve: Allow your crispy chocolate rolls to cool slightly on a wire rack before serving them warm.