Preheat your oven to 350°F (175°C) and prepare a jelly roll pan by lining it with parchment paper.

In a mixing bowl, whisk together all-purpose flour, unsweetened cocoa powder, baking powder, and salt until thoroughly combined.

In a separate bowl, beat together large eggs and granulated sugar on high speed until thick and pale, about 3-5 minutes. Gently mix in vegetable oil, milk, and vanilla extract.

Carefully fold the dry ingredients into the wet mixture using a spatula until smooth. Transfer to your prepared jelly roll pan.

Place the pan in the preheated oven and bake for 10-12 minutes. The cake should spring back when gently touched.

Invert the hot cake onto a clean kitchen towel sprinkled with granulated sugar and roll it up from one short end. Allow it to cool completely.

Beat together creamy peanut butter and powdered sugar. Add heavy cream and vanilla extract, mixing until smooth. Fold in chopped peanut butter cups.

Unroll the cooled cake and spread the peanut butter filling evenly. Re-roll the cake tightly without the towel.

Heat heavy cream in a saucepan until just simmering. Pour over semi-sweet chocolate chips and stir until smooth to create ganache.

Spread the ganache over the rolled cake and chill in the refrigerator for at least 30 minutes.

Slice the roll into portions and serve, optionally garnishing with extra chopped peanut butter cups.