Active time: 25 min Start to finish: 2 1/4 hr (includes cooling)

　　

Ingredients

Makes 8 servings

　　1/2 cup mild olive oil

　　1 cup chestnut flour* plus additional for dusting

　　3/4 cup hazelnuts (3 1/2 oz)

　　1/2 teaspoon baking powder

　　1/2 teaspoon baking soda

　　1/2 teaspoon salt

　　3 large eggs, separated

　　1/2 cup mild honey

　　1/4 cup sugar

　　

Special Equipment

a 9- to 9 1/2-inch (24-cm) springform pan

　　

Step 1

Put oven rack in middle position and preheat oven to 350°F. Oil pan and dust with chestnut flour, knocking out excess.

　　

Step 2

Toast hazelnuts in a shallow baking pan until fragrant and interior of nuts are pale golden, 10 to 12 minutes. Rub nuts in a kitchen towel to remove any loose skins (some skins may not come off). Cool nuts to room temperature and chop medium-fine.

　　

Step 3

Sift together chestnut flour, baking powder, and salt in bowl, then stir in nuts.

　　

Step 4

Beat together egg yolks, oil, honey, and 2 tablespoons sugar with an electric mixer at high speed until thick and pale, about 5 minutes in a stand mixer or 8 minutes with a handheld. Add flour mixture and mix at low speed just until flour is moistened.

　　

Step 5

Beat egg whites and a pinch of salt in another medium bowl with cleaned beaters at medium-high speed until they form soft peaks. Add remaining 2 tablespoons sugar a little at a time, beating, and beat until whites just hold stiff peaks. Fold one third of whites into batter to lighten it, then fold in remaining whites gently but thoroughly. Spread batter in pan and rap pan on work surface once to release any large air bubbles. Bake 30 minutes, then loosely cover with foil and bake until a wooden pick or skewer inserted in center of cake comes out clean, 10 to 15 minutes more. (Cake is naturally dark.)

　　

Step 6

Transfer cake in pan to a rack and cool 30 minutes, then remove side of pan and cool completely. Remove cake from bottom of pan to serve if desired.

　　Cooks' note:

　　Cake can be made 3 days ahead and kept in an airtight container at room temperature.