Preheat the oven to 180°C (350°F). Line a jelly roll pan with parchment paper, leaving a little overhang on the sides. Lightly grease the paper to prevent sticking.

In a large bowl, beat the eggs and granulated sugar until pale, thick, and fluffy. This step is important because it adds air to the batter. Add the vanilla extract and mix gently.

Sift together the flour, cocoa powder, baking powder, and salt. Gradually fold the dry ingredients into the egg mixture using a spatula. Mix gently until just combined to keep the batter light.

Pour the batter into the prepared pan and spread it evenly. Bake for 10–12 minutes, or until the cake springs back lightly when touched.

While the cake is still warm, carefully lift it out using the parchment paper. Roll the cake gently from the short side, with the parchment paper or a clean kitchen towel inside. Let it cool completely in this rolled shape.

In a bowl, mix the peanut butter, powdered sugar, vanilla extract, and cream cheese (if using) until smooth. In a separate bowl, whip the heavy cream until soft peaks form, then gently fold it into the peanut butter mixture. Stir in the chopped peanut butter cups or chocolate chips.

Carefully unroll the cooled cake. Spread the peanut butter filling evenly over the surface, leaving a small border around the edges. Gently roll the cake back up without the parchment paper.

Heat the heavy cream until just warm (not boiling). Pour it over the chopped chocolate and let it sit for 1–2 minutes, then stir until smooth and glossy.

Place the rolled cake on a wire rack or serving plate. Pour the ganache over the top, letting it drip down the sides for a smooth finish.

Refrigerate the cake for at least 30 minutes to set. Decorate with chopped peanut butter cups, chocolate drizzle, or crushed peanuts if desired.

Use a sharp knife to slice the cake cleanly. Serve chilled or slightly softened at room temperature for the best flavor and texture.