From World Wide Recipes:

 

The "black" in the title of this recipe refers to the fact that the
almonds are unblanched, making the cake more economical,
if not quite as pretty, as similar cakes calling for blanched nuts.

Black Almond Cake (Schwarze Mandeltorte)

1/2 lb (225 g) unblanched almonds, finely ground in
a food processor
1 cup (250 ml) sugar
1 tsp (5 ml) ground cinnamon
8 eggs
Confectioner's sugar for garnish (optional)
Sweetened whipped cream for garnish (optional)

Combine the almonds, sugar, and cinnamon in a mixing bowl.
Add the eggs one at a time, mixing thoroughly before adding the
next. Pour into a greased 9-inch (23 cm) springform pan and bake
in a preheated 325F (165C) oven until set in the center, 45 to 50
minutes. Serve garnished with confectioner's sugar or whipped
cream if desired. Serves 6 to 8.