1½ cups hazelnuts, toasted and skins rubbed off
1½ cups all-purpose flour, (plus more for the cake pan)
1 teaspoon baking powder
¼ teaspoon salt
1 cup sugar, plus 2 tablespoons
6 tablespoons butter, softened (plus a bit for the cake pan)
3 large eggs
1 tablespoon extra-virgin olive oil
½ tablespoon orange zest, finely grated
1 cup milk, at room temperature
4 tablespoons semisweet chocolate, chopped by hand in small pieces
powdered sugar or whipped cream, for garnish
Chop the hazelnuts in a food processor or mini-chopper to small bits-not to a powder. Whisk or sift together the flour, baking powder and salt. Butter and flour the cake pan. Preheat the oven to 350° with a rack in the center.
In the mixer, cream the sugar and butter together until light, smooth and fluffy; scrape the sides of the bowl as needed. Incorporate the eggs, olive oil and orange zest in several additions, blending each in at slow speed, scraping the bowl then beating at high speed for a couple of minutes to lighten.
On slow speed, incorporate the dry mix in several additions, alternating with splashes of milk. Scrape the bowl when both are added and beat briefly on high. Fold in the chopped nuts and chocolate by hand and blend in well.
Scrape the batter into the cake pan and smooth the top. Bake until a cake tester comes out clean, about 45 minutes. The top should be lightly browned and just spring back to a light touch.
Cool on a wire rack for 30 minutes or so, remove the side ring of the springform and let the cake cool completely. Cut in wedges and serve, topped with powdered sugar or whipped cream.
The torte will keep in the refrigerator for a week, well wrapped in plastic, or freeze it for longer storage. When serving torte that has been chilled or frozen, toast the cut pieces in the oven (or toaster oven) to bring out the flavors.