Instructions

• Preheat the oven to 350°F (175°C). Position a rack in the center of the oven.
• Separate the 6 eggs into whites and yolks. Place the whites in a clean, dry mixing bowl and set the yolks aside.
• Divide the 225 g sugar into two equal portions (112.5 g and 112.5 g).
• In a stand mixer fitted with the whisk attachment, add the egg whites and 112.5 g of the sugar. Whip on high speed until stiff, glossy peaks form, about 6–7 minutes. Transfer the meringue to the refrigerator while you prepare the rest of the batter.
• Place the 280 g bittersweet chocolate in a heatproof bowl set over (not touching) simmering water (double boiler). Stir until completely melted and smooth. Remove from heat and let the chocolate cool slightly while you proceed (it should be warm, not hot).
• In the stand mixer (use the whisk or paddle attachment), add the 280 g softened unsalted butter and the remaining 112.5 g sugar. Whisk on high speed until the mixture is light and fluffy, about 4–5 minutes.
• With the mixer running on low-to-medium speed, add the 6 egg yolks one at a time, waiting until each yolk is incorporated before adding the next. Scrape down the bowl as needed.
• Remove the bowl from the mixer. Gently fold in the 340 g superfine almond flour with a spatula until evenly combined.
• Fold the cooled melted chocolate into the almond-butter-yolk mixture until uniformly mixed and smooth.
• Carefully fold the chilled meringue into the chocolate-almond batter in two additions, using gentle motions to preserve as much air as possible until no white streaks remain.
• Prepare a 10-inch springform pan: butter the sides and bottom (use some of the softened butter) and line the bottom with a circle of parchment paper. Spoon the batter into the prepared pan and smooth the top.
• Bake at 350°F (175°C) for 40–42 minutes, until the top is set and a thin crust has formed (the center may still be slightly moist).
• Remove the cake from the oven and allow it to cool completely in the pan on a wire rack. When cool, remove the springform ring and transfer the cake to a serving plate.
• Dust the cooled cake with powdered sugar before serving.