Make the cake roll

1. Preheat oven to 350°F. Line a 17×12-inch jelly roll sheet pan with parchment paper. Make sure the parchment paper sticks up at least an inch above the sides of the pan on all sides. You’ll use the parchment paper later to lift the cake out of the pan and roll it up.
2. Combine flour, cocoa powder, baking powder, espresso powder and salt in a medium sized bowl. Set aside.
3. Add the eggs, sugar and vanilla extract to a large mixer bowl and whip on high speed with the whisk attachment until pale, fluffy and thickened, about 4 minutes.
4. Add half of the dry ingredients to the whipped egg mixture and gently fold together until mostly combined. Add the remaining dry ingredients to the egg mixture and gently fold together until just well combined.
5. Combine the milk and butter and heat in the microwave until the butter is melted and the mixture is very hot. It doesn’t have to be boiling, but it should be very hot. Add the hot milk mixture to the batter and gently whisk together until well combined.
6. Spread the cake batter evenly into the prepared pan and bake for 10-12 minutes, or until the top of the cake springs back when touched and a toothpick inserted comes out clean.
7. Remove the cake from the oven and immediately lift the cake out of the pan using the parchment paper and place it on the counter. While the cake is hot, use the parchment paper the cake was baked in and start at the shorter end of the cake to slowly roll the cake up.
8. You can just set the cake roll aside to cool completely, if you like. But to help avoid having the cake crack later, I like to unroll and re-roll the cake a few times during cooling to help it keep its elasticity. I first unroll it after about 5 minutes, then after another 5 minutes, and again after another 10 minutes. From there, I might roll it out 2-3 more times after 10-15 minute intervals. It should take about an hour to an hour and a half to cool completely, depending on the temperature of your home.

Make the filling

1. When the cake has cooled and is ready to be filled, make the whipped cream filling. Add the heavy whipping cream, powdered sugar and vanilla extract to a large mixer bowl and whip on high speed until it reaches stiff peaks.
2. Unroll the cake roll very carefully, looking out for areas where it may be sticking to the parchment paper to release it. You can use an offset spatula or something similar and run it along the parchment paper as you unroll the cake to help release it as it unrolls. I also like to gently lift up before I roll back, to give the cake a chance to release.
3. Spread the filling evenly onto the unrolled cake, then roll it back up without the parchment paper. Wrap it up in plastic wrap with the seam side down and refrigerate for at least an hour to firm up.

Finish it off

1. When you’re read to decorate the cake, make the chocolate ganache. Add the chocolate to a medium sized bowl and set aside. Heat the cream in the microwave just until it begins to boil, then pour it over the chocolate.
2. Allow the chocolate and cream to sit for a few minutes, then stir until smooth.
3. Remove the chilled cake roll from the fridge and plastic wrap and place on a cooling rack set over a large cookie sheet or pan.
4. Pour the chocolate ganache over the cake, spreading it to cover the entire cake, as needed.
5. You can serve the cake roll immediately, or refrigerate until the chocolate coating is cold and firm, 1-2 hours. Slice the cake roll and serve.
6. Cake roll is best stored well covered and eaten within 3-4 days.