Step 1

Preheat oven to 350°F (177°C). Make sure you have a bottom oven rack and a center oven rack in place for step Grease an 8-inch round cake pan, line with parchment paper rounds, then grease the parchment paper. Parchment paper helps the cakes seamlessly release from the pans. (If it’s helpful, see this parchment paper rounds for cakes video & post.) The cake WILL stick unless it’s lined and generously greased. (Trust me!)

Step 2

Cut the butter into pieces so it melts evenly. Place in a large heat-proof bowl. Add chopped chocolate. Melt in 20 second increments in the microwave, stirring after each increment until completely melted and smooth. Let cool for 2-3 minutes. You can use a double boiler for this step if desired.

Step 3

Whisk the sugar, espresso powder, and vanilla extract into the chocolate mixture. Whisk in the eggs until smooth. The mixture will be heavy and tacky, like brownie batter. Whisk in the cocoa powder, salt, and baking powder (if using).

Step 4

Pour and spread batter into prepared cake pan.

Step 5

Place a large metal roasting pan or baking dish on the bottom oven rack. Do not use glass. Pour boiling water about 2 inches up the sides of the pan. (I just boil a kettle of water.) Quickly place the cake on the center rack and shut the oven door, trapping steam inside. The steamy oven helps guarantee an extra moist cake.

Step 6

Bake for 30 minutes until the edges are set. The cake is done when a toothpick inserted into the center of the cake comes out clean OR comes out with just a few moist crumbs. It’s important to not over-bake this cake, which dries it out. Begin checking it at 25 minutes. Don’t be alarmed if the cake rises extra tall around some of the edges and slightly cracks—this is normal (it’s the eggs expanding) and will flatten out as it cools.

Step 7

Remove from the oven, place cake on a cooling rack, and cool for only 10 minutes in the cake pan. Run a sharp knife around the edges to help release the warm cake, then quickly invert it onto a serving plate or cake stand. (If it cools completely in the pan, it’s very difficult to release from the pan.) Cake will be a little crumbly on the edges. Cool completely. I usually stick it in the refrigerator for 1-2 hours.

Step 8

Once the cake is cool, top with your choice of toppings. My suggestions are listed above this recipe. I love it with my mocha whipped cream.

Step 9

Using a fork, mix the espresso powder and warm water together in a very small bowl. Cool down for a few minutes. Using a hand mixer or a stand mixer fitted with a whisk attachment, whip the heavy cream, sugar, cocoa powder, and espresso mixture on medium-high speed until medium peaks form, about 3-4 minutes. Medium peaks are between soft/loose peaks and stiff peaks and are the perfect consistency for topping and piping on desserts. Serve cake with whipped cream or pipe it on top. I used Ateco 849 piping tip. Decorate with raspberries and a dusting of confectioners’ sugar, if desired.

Step 10

Cover and store leftover cake in the refrigerator for up to 5 days.