Cashew and potato cake
- 3 medium-sized boiling potatoes (about 1 pound), peeled and quartered
- 2 tablespoons + 3 x ¼-pound sticks unsalted butter, softened
- 2 tablespoons flour
- 2 cups sugar
- 2 cups roasted unsalted cashews, finely chopped or pulverized in a blender or with a nut grinder
- 2 teaspoons finely grated fresh lemon peel
- 2 teaspoons finely grated fresh orange peel
- 9 egg yolks
- 4 egg whites
- Drop the potatoes into enough boiling water to cover them completely and cook briskly, uncovered, until they are soft enough to be easily mashed with a fork.
- Drain, then mash the potatoes vigorously with a fork or put them through a ricer set over a bowl.
- Set the potatoes aside to cool to room temperature.
- Preheat the oven to 350°F.
- With a pastry brush, spread 2 tablespoons of the softened butter evenly over the bottom and sides of a spring form cake pan 9 inches wide and 3 inches high.
- Sprinkle the pan with the flour, tipping it from side to side to spread the flour evenly.
- Then invert the pan and rap it sharply to remove the excess flour.
- In a deep bowl, cream the 3 sticks of softened butter and 2 cups of sugar together by beating and mashing them against the sides of the bowl with the back of a spoon until they are light and fluffy.
- Beat in the potatoes, cashews, lemon peel and orange peel.
- Add the egg yolks, 1 at a time, stirring after each addition, and continue stirring until the mixture is well blended.
- With a wire whisk or a rotary or electric beater, beat the egg whites until they are stiff enough to form firm, unwavering peaks on the beater when it is lifted from the bowl.
- Stir a heaping tablespoon of the whites thoroughly into the potato mixture.
- Then spoon the remaining egg whites over the mixture and, with a rubber spatula, fold them together gently but thoroughly.
- Pour the batter into the buttered and floured pan, spreading it and smoothing the top with the spatula.
- Bake in the middle of the oven for about 1 hour, or until the top is brown and a skewer inserted into the middle of the cake comes out clean.
- Let the cake cool for 5 minutes.
- Then remove the sides of the pan and with the help of a large metal spatula slide the cake off the base onto a wire rack.
- Serve the bolo polana while it is still slightly warm, or let it cool to room temperature before serving.