1. Preheat the oven to 350°F. Line a 10×15-inch jelly roll pan with parchment paper and lightly grease it.

2. In a large bowl, beat the eggs and granulated sugar until pale and slightly thickened.

3. Sift in the cocoa powder, flour, baking powder, and salt. Fold gently until combined, then stir in the vanilla extract.

4. Spread the batter evenly into the prepared pan and bake for 10 to 12 minutes, until the cake springs back lightly when touched.

5. While the cake bakes, lay a clean kitchen towel on the counter and dust it with powdered sugar.

6. Turn the hot cake out onto the towel, peel off the parchment paper, and roll the cake up with the towel from the short end. Let it cool completely.

7. In a mixing bowl, beat the peanut butter and softened butter until smooth.

8. Add the powdered sugar and vanilla extract, then mix until fluffy.

9. Add the heavy cream a little at a time until the filling is smooth and spreadable.

10. Fold in the chopped mini peanut butter cups.

11. Carefully unroll the cooled cake and spread the peanut butter filling evenly over the surface, leaving a small border around the edges.

12. Roll the cake back up without the towel and place it seam side down.

13. Chill for 30 minutes to help it set.

14. Drizzle with melted chocolate, slice, and serve.