Place rack in lower third of oven and heat to 375°F. Place a round of parchment paper in the bottom of an 8-inch springform pan and spray the sides with vegetable oil spray.
In a food processor or blender, grind the almonds with the flour until very fine. Set aside.
Combine the chopped chocolate, cocoa, and 3/4 cup of the sugar in a large mixing bowl. Pour in the boiling water and whisk until the mixture is smooth and chocolate is completely melted. Whisk in the egg yolks and brandy. Set aside.
Combine the egg whites and cream of tartar in a medium mixing bowl. Beat on medium speed until soft peaks form. Gradually sprinkle in the remaining sugar and beat on high speed until stiff but not dry. Whisk the flour and the almonds into the chocolate. Fold about a quarter of the egg whites into the chocolate mixture to lighten it. Fold in the remaining egg whites. Scrape the batter into the pan and level the top if necessary.
Bake at 375°F for 30 to 35 minutes, or until a toothpick or wooden skewer inserted into the center comes out with a few moist crumbs clinging to it. Cool in the pan on a wire rack. Torte will sink like a soufflé.
Taking care not to break the edges of the torte, slide a knife between the torte and the pan and run it around the pan to release the cake completely. Invert the cake onto a plate and remove the pan and the parchment paper liner. Turn the cake right side up on a cardboard circle or platter. The torte may be stored, covered, at room temperature for 1 day or frozen for up to 2 months.
Sieve powdered sugar over the top.