Preparation:
Bake or microwave potato until soft. Force pulp through a coarse sieve or potato ricer. There should be 1 cup lightly packed. Set aside to cool. Preheat oven to 350F. Butter sides of an 8 1/2-inch spring form pan, line base with a circle of baking parchment; butter the parchment. Using a nut mill, grind almonds to powder, stir in baking powder; set aside. Beat egg whites until they start to stiffen, sprinkle with half of the sugar, a little at a time, and continue beating until stiff and glossy. Beat butter with remaining sugar, then beat in egg yolks, brandy, and almond extract. Using a large rubber spatula, fold in potato, ground almonds and egg whites. Spoon into prepared pan; bake for 35 to 40 minutes, until a tester comes out dry. Let cool in pan for 10 minutes. Run a knife blade around edge before releasing sides of pan. Place cake, on the base, on a rack and let cool completely. Cake will sink slightly in the middle. Reverse cake onto a plate, peel off paper and place right side up on a serving plate. Dust with powdered sugar before serving. MARZIPAN "POTATOES": You'll need 4 ounces marzipan or almond paste and powdered unsweetened cocoa. Pinch off pieces of marzipan and roll into elongated balls, each about the size of a large marble. Make these slightly irregular, like tiny new potatoes. Roll in cocoa to simulate brown potato skin. Cut several in half to show the white interior. Arrange a little group on top of the cake, and place the rest in twos and threes around the edge of the plat |
