We’ve all seen chocolate bombes in fancy pastry shops or French cookbooks. And they look too difficult to make, right? This recipe, while just as impressive, removes the fuss. We use a simple chocolate jelly-roll cake and cut it into strips. Strips of sheet cake are easy to manipulate and sturdy enough to encase the mousse filling. We use the strips to line a mixing bowl (no fancy mold required). Our mousse filling gets its intense chocolate flavor from bittersweet chocolate enhanced with cocoa powder, espresso powder, and brandy. And for a smooth and glossy finishing touch, we drizzle a chocolate glaze (that comes together in the microwave) over the top of the filled cake.
Cut the cake crosswise into eighteen 1-inch-wide strips.
Line a 1½-quart bowl with plastic wrap, letting several inches of excess drape over the edge. Line the bowl with cake strips, placed side by side. Fill in any holes with additional pieces of cake (trimmed to fit) as needed. Trim any cake strips that overhang the bowl.
Scrape the filling into the cake-lined bowl and cover the top completely with the remaining cake strips and trimmed pieces of cake. (Note that you may have extra pieces of cake left over.) Wrap the bowl tightly in plastic wrap and refrigerate.
After chilling and unmolding, pour the glaze over the bombe to coat evenly.