16ouncesdark or semi-sweet dairy free chocolate1coarsely chopped
1cup(227g) salted vegan butter2cut into 16 pieces
Adjust an oven rack to the lower-middle position and preheat the oven to 325°F (163ºC).
Wrap the outside of an 8" or 9" springform pan with heavy duty foil, being sure to cover the bottom. Line the pan with parchment paper and spray the parchment and sides of the pan liberally with non-stick spray. Place this pan in a large roasting pan or any pan that's larger than the springform. Set aside.
Place the chocolate and butter into a large saucepan and melt over medium heat, stirring constantly with a spatula or wooden spoon until completely melted. Remove from heat, pour into a large bowl, and set the bowl aside.
In a large bowl with a handheld mixer or the bowl of a stand mixer fitted with the whisk attachment, beat the eggs at high speed until the volume doubles and egg mixture lightens in color. This will take about 5 minutes.
Fold about ⅓ of the egg foam into the chocolate mixture using a large rubber spatula until almost homogenous. Fold in half of the remaining egg foam, and then the last half of the foam, until the mixture is totally homogenous.
Pour the batter into the prepared pan, then pour hot water into the roasting/larger outside pan until it is about halfway up the sides of the springform pan. Bake the cake for 35-40 minutes, until the cake has risen slightly, the edges are just beginning to set, and a thin-glazed crust (similar to a brownie) has formed on the surface. If you want to check the internal temperature for proper doneness, look for 140°F (60ºC) on a digital instant-read thermometer. Remove the springform pan from the water bath and allow to cool to room temperature on a wire cooling rack. Cover the cake and refrigerate at least 4 hours. preferably overnight.
When you are ready to serve the cake, remove it from the refrigerator about 15 minutes before you want to serve it. Carefully remove the outside ring of the springform pan, invert the cake onto a sheet of waxed paper, peel off the parchment paper, and reinvert the cake onto a serving platter. Dust your cake with cocoa powder or powdered sugar, or leave plain. Serve with berries, chocolate syrup, salted caramel sauce, homemade whipped cream, ice cream, buttercream, or anything else you would pair with chocolate. Store leftovers in the refrigerator up to 5 days.
Dairy free chocolate: if you don't need to keep this cake dairy free, use regular chocolate.
Salted vegan butter: if you use unsalted butter (vegan or otherwise), add ½ teaspoon of salt.
Make a smaller cake: we have successfully cut this down to ¼ of the recipe and baked it in a 4" springform pan. This size cake is perfect for 2-4 people to share.