Hazelnut Cake with Zabaglione

Method

1. Preheat the oven to 175–180°C (350°F). Butter a 28 cm round cake pan and coat it with coarse hazelnut granules; set aside.
2. Separate the eggs: place the whites in a clean, grease-free bowl of a stand mixer and the yolks in a separate bowl (reserve for the zabaglione).
3. Make the meringue: start whipping the egg whites on medium speed. When they become foamy and white, gradually add the sugar, a spoonful at a time, continuing to whip until stiff peaks form. The meringue should quadruple in volume and form a beak on the whisk.
4. Reduce the mixer speed to low and slowly pour in the hot honey (heated until just boiling) in a thin stream. Then increase speed again and whip for about 1 minute until the meringue is glossy and stiff.
5. Sift together the cocoa powder and potato starch into a bowl. Grind the hazelnuts into a fine flour (reserve some for coarse granules).
6. Gently fold the hazelnut flour and coarse hazelnut granules into the meringue, a little at a time, using a spatula with a motion from bottom to top, rotating the bowl 90° each time. Be careful not to deflate the meringue.
7. Fold in the sifted cocoa and potato starch mixture in the same gentle manner until just combined.
8. Pour the batter into the prepared cake pan, leveling the surface. Sprinkle the reserved coarse hazelnut granules on top.
9. Bake for 20 minutes, or until a toothpick inserted in the center comes out clean. The cake should be springy to the touch.
10. Remove from the oven and let cool in the pan for 7–8 minutes, then turn out onto a wire rack to cool completely.
11. While the cake bakes, prepare the zabaglione: In a large stainless steel bowl, combine the egg yolks and sugar (1 tablespoon of sugar per yolk). Whisk vigorously off the heat until the yolks lighten in color.
12. Place the bowl over a bain-marie (the bowl should not touch the simmering water). Continue whisking vigorously, gradually adding the Vin Santo (warmed to about 35°C, not boiling). Whisk for about 10 minutes until the zabaglione is thick, foamy, and creamy.
13. Remove the bowl from the heat and place it over a bowl of ice water to stop the cooking, whisking until it cools and becomes glossy. This prevents a skin from forming.
14. Serve the hazelnut cake slices with a generous spoonful of zabaglione on the side.