Extra-Fudgy Flourless Chocolate Cake

Directions

1. Heat the oven to 350°F. Butter the bottom of an 8-inch round springform pan—but don’t butter the sides of the pan, which would prevent the cake from rising properly.
2. Melt the butter in a small pot over medium-low heat. As soon as it has totally melted, turn off the heat, then add the chocolate. Gently swirl the pot so all the chocolate gets covered in warm butter. Let this sit for a couple minutes, then stir until the chocolate is completely melted, smooth, and shiny.
3. Combine the egg yolks, ½ cup sugar, and salt in a large bowl. Whisk until the mixture is a very pale yellow (this shouldn’t take more than a couple minutes).
4. Add the egg whites to the bowl of a stand mixer fitted with the whisk attachment. Beat on low, then slowly increase the speed to medium, then to medium high. As soon as the egg whites start to turn foamy and puffy, slowly start streaming in the sugar. (A steady flow is fine, just keep it slow.) Once all the sugar has been added, continue to beat until glossy, mostly-stiff peaks form.
5. Whisk the ½ cup cream until stiff peaks form, but be careful not to over-whip to the point of graininess. (I like to do this by hand—it doesn’t take as long as you’d think and makes you feel accomplished.)
6. Add a small pour of the chocolate-butter mixture to the egg yolk–sugar mixture. Stir with a silicone spatula. Add a little more and stir. Continue doing this until you’ve incorporated all the chocolate-butter mixture. Now add a spoonful of the meringue and gently fold until mostly combined (some remaining streaks of white are good—it means you haven’t overmixed). Add a little more and, again, fold until mostly combined. Continue doing this until you’ve added all the meringue and it’s mostly combined, taking care to not overmix or deflate the batter. Now fold in the whipped cream in the same way.
7. Pour the batter into the prepared springform pan and smooth the top. Add the pan to a rimmed baking sheet (this makes rotating easier) and get it in the oven.
8. Bake for 45 to 50 minutes, rotating the pan halfway through, until the top of the cake is starting to crack around the perimeter and the center is no longer wobbly. Cool completely in the pan on a wire rack. (The center will sink into a dramatic crater—that’s good.)
9. When you’re reading to eat, whip the remaining 1 ½ cup cream until slouchy, soft peaks form. Add this to the sunken center of the cake, spreading and swirling it, but making sure to leave a distinct chocolate cake border.
10. Shave more bittersweet chocolate on top, if you’d like, before serving. Run a dull knife around the edge of the perimeter of the cake, then unmold the springform. Use a serrated knife to slice into big wedges.