How to Make a Chocolate Swiss Roll (with Video!)

1. Preheat oven to 350F (175C) and lightly spray a jelly roll pan (10x15") with baking spray, then line with parchment paper. Set aside.
2. In a large bowl, whisk together flour, cocoa powder, baking soda, baking powder, salt. Set aside.
3. In a separate bowl, combine egg yolks, ½ cup (100g) granulated sugar, brown sugar, melted butter, and vanilla extract. Whisk vigorously until mixture is lightened in color (about 30-60 seconds). Add flour mixture to the bowl and stir together until well-combined (mixture will be thick).
4. In yet another large, completely clean, dry, and grease-free bowl, beat egg whites to soft peaks (see note). Gradually (about 1 Tablespoon at a time) add remaining ¼ cup/(50g) granulated sugar until you have stiff peaks.
5. Briefly stir chocolate mixture in case it has thickened, then gently fold in egg whites until completely combined (be gentle, deflate your egg whites as little as possible, but the mixture should look smooth).
6. Spread batter evenly into prepared pan and bake on the center rack of your oven for 15-18 minutes or until the cake springs back when very lightly touched.
7. While cake is baking, generously and thoroughly dust a tea towel or clean (cloth) kitchen towel evenly with about 2 Tablespoons of cocoa powder (this will keep the cake from sticking to it when you unroll and will prevent cracks!).
8. When the cake has finished baking, allow it to rest for 2 minutes then quickly and carefully invert onto prepared towel. Carefully peel off parchment paper (if any of the parchment ended up beneath the cake, very gently tug it out before removing.
9. Now very gently, starting with one of the shorter ends of the cake, roll it into the towel to form a log (see image or video if needed). Very carefully transfer to a cooling rack and allow to cool completely. While cooling, prepare your filling. I like to use Ermine icing (linked in the instructions above), but whipped cream or even cream cheese frosting (reduce the sugar to only two cups) are other good options.
10. Once the swiss roll has cooled, very carefully unroll it in the towel. Don’t sweat any small cracks, you can patch them together with your icing.
11. Evenly spread filling over the roll (I usually have a little ermine icing leftover) then very carefully re-roll the log.
12. Transfer to a wax-paper lined serving platter and place in the fridge while you prepare the chocolate glaze.

Chocolate Glaze

1. Combine chocolate chips and shortening in a heatproof bowl or large heatproof measuring cup. Microwave in 20-second intervals, stirring well in between, until chocolate is completely melted and mixture is smooth.
2. Allow to cool for 10-15 minutes, then remove roll from fridge and evenly pour chocolate overtop. Use an offset spatula to evenly distribute the glaze, then return to the refrigerator and allow chocolate to harden before cutting and serving.