Serves 8 to 10

This cake is gluten-free but no one will suspect because the cake and ganache are so rich and fudgy. Thomas Keller’s Cup 4 Cup gluten-free flour is pure genius.

INGREDIENTS

• 1 pound plus 3 ounces bittersweet chocolate such as Lindt, broken into chunks
• 10 tablespoons (1 ¼ sticks) unsalted butter, cut into pieces, at room temperature
• 1 tablespoon Cup 4 Cup gluten-free flour
• 1 ½ tablespoons sugar
• 1 teaspoon instant coffee granules
• ¼ teaspoon kosher salt
• 4 extra-large eggs, at room temperature, separated
• ¼ cup heavy cream
• Coffee or vanilla ice cream, for serving

DIRECTIONS

1. Preheat the oven to 425 degrees.
2. Grease an 8-inch springform pan and line the bottom with parchment paper.
3. Place the one pound of chocolate in a large heat-proof bowl set over a pan of simmering water and stir occasionally until the chocolate is melted. Off the heat, immediately stir in the butter, flour, sugar, coffee granules, and salt with a rubber spatula. Whisk in the egg yolks until smooth.
4. Place the egg whites in the bowl of an electric mixer fitted with the whisk attachment and beat until they form soft peaks.
5. Scrape the egg whites into the chocolate mixture and fold them in very carefully with a rubber spatula, just until combined. Scrape the mixture into the prepared pan, smooth the top, and bake for 15 minutes exactly. (Be sure your oven temperature is accurate!)
6. Turn the oven off and leave the cake in the oven, leaving the door slightly ajar. Allow the cake to cool in the oven for 1 hour. The cake will sink in the middle. Carefully release the sides of the pan and slide the cake onto a flat serving plate or cake stand.
7. Place the 3 ounces of chocolate and the heavy cream in a heat-proof bowl set over a pan of simmering water and heat just until the chocolate melts, stirring occasionally. Add a drop of cream if the mixture is too thick to pour. Pour the chocolate onto the sunken part of the cake, leaving the edge unfrosted. Allow to cool and serve warm or at room temperature with a scoop of ice cream.
   Note: You can certainly make this with1 tablespoon all-purpose flour instead of gluten-free flour.

MAKE IT AHEAD

Prepare the cake and allow it to sit at room temperature for up to 6 hours.