vegetable oil and matzo meal, finely ground for the cake pan
1/2 pound bittersweet chocolate, chopped
6 large eggs, separated
1/2 cup sugar
pinch of salt
1 teaspoon vanilla extract
1 cup ground almonds
2 teaspoons espresso powder
1) Preheat the oven to 350 degrees. Lightly oil a 9-inch spring-form cake pan and dust with matzo meal.
2) Melt the chocolate in a double boiler, or in a microwave on low stirring every 20 seconds until melted and just smooth.
3) Beat the egg yolks with sugar and salt until pale yellow. Stir in the ground almonds, melted chocolate, vanilla, and espresso powder.
4) In a separate bowl, beat the egg whites until they just hold stiff peaks but are not dry. Stir ¼ of the whites into the chocolate and egg mixture to lighten, then fold in remaining whites gently but thoroughly.
5) Transfer the batter to the cake pan and bake in the middle of the oven for about 45 minutes until puffed and a toothpick inserted into the center comes out clean.
6) Cool on a rack. Run a knife around sides to loosen sides of cake, remove pan sides and serve cake at room temperature on a platter. Can be made a day in advance, covered tightly in foil.