If you have only two or three 8-inch pans, and if they will fit on the same rack, adjust the rack to the lowest position in the oven. If you have more pans than will fit on one rack, adjust two racks, one to the lowest position and the other closer to the middle. Preheat oven to 350 F. Cut seven circles of wax paper to fit the 8-inch pans. Butter as many pans as you have, line them with the papers and butter the papers. Set the prepared pans aside and reserve the extra circles of wax paper. In the small bowl of an electric mixer beat the egg yolks and about half of the sugar at high speed for about 5 minutes until very pale and thick. On low speed gradually add the flour and beat, scraping the bowl with a rubber spatula and beating only until the flour is incorporated. The mixture will be very thick. Remove it from the mixer (use your index finger to scrape the beaters clean.) Add the salt to the egg whites in the large bowl of the electric mixer. With clean beaters, beat until the whites hold a soft shape. Reduce the speed to moderate, gradually add the remaining sugar, then increase the speed again and beat until the whites hold a firm shape. Add about 1/2 cup of the beaten whites to the yolks and stir it in. Then stir in another 1/2 cup. Then, adding about 1/2 cup at a time, fold in all but about 2 cups of the whites. Fold the yolks into the remaining whites. You will have about 6 1/2 cups of batter to make seven layers, therefore each layer should use a scant 1 cup of batter. It is not necessary to measure the amount you can approximate it. Spread the batter smoothly all the way to the edges of the prepared pans it must touch the sides of the pans all the way around, and it should be smooth. The layers should bake about 15 minutes. If you are using more than one rack, the pans must be reversed top to bottom once during baking; each layer should spend some time on the lowest rack so that the bottom bakes well. When done, the tops will be barely colored, and the layers may show signs of beginning to come away from the pans at the edges. Spread out a large, smooth (not terry cloth) cotton or linen towel. When the layers are done, cut around the sides to release and then invert the layers onto the towel. Remove the pans and peel off the papers. If the bottoms are baked dry enough the papers will peel off in one piece; if they don't, it is all right to tear the papers off, once section at a time. (The bottoms should be a little darker than the tops.) With your hands immediately turn the layers right side up the tops of the layers are sticky and would stick to the towel. Let stand until cool. The remaining batter may wait uncovered at room temperature, but don't waste any time getting it all baked. Wash the pans, prepare them as before, and bake the remaining layers. Prepare a flat cake plate by lining the sides with four strips of wax paper. Place one layer right side up on the plate, checking to be sure that the papers touch the cake all around. If you have a cake-decorating turntable or a lazy Susan, place the cake plate on it. Prepare the filling and icing.

Bittersweet Chocolate Filling and Icing Place the chocolate in the top of a small double boiler over hot water on moderate heat. Cover until partially melted, then uncover and stir until completely melted. Meanwhile, in a small saucepan, mix the water with the sugar and instant coffee. Place over moderate heat and stir until the sugar is dissolved and the mixture comes to a boil. Also meanwhile, in the small bowl of an electric mixer, beat the egg yolks at high speed until they are pale lemon-colored. When the sugar/coffee syrup is ready, turn the mixer speed to low and very slowly, in a thin stream, beat the syrup into the yolks. Then add the warm melted chocolate and beat only until smooth it will be very thick. Now, beating slowly, add the butter, one or two pieces at a time, and beat well until completely blended. With a long, narrow metal spatula spread a very thin layer of the buttercream over the cake, spreading it smoothly all the way to the edges. The layers of filling must be thin or there will not be enough to cover the top and sides this amount is just right if you spread it thin enough. All the layers should be placed right side up except the top one, which should be upside down to insure a perfectly flat top. After filling all the layers, cover the top and sides. But just before spreading the icing on the top and sides of the cake, if it is not silken smooth, and if you have a food processor, process the icing (use the metal blade) for a few seconds and like magic it will become completely smooth. Then, with a long, narrow metal spatula, spread the icing smooth. Remove the wax paper strips by pulling each one out toward a narrow end. Refrigerate for several hours to set the icing. The cake may be cold when it is served or at room temperature. It should be cut with a sharp, heavy knife. If you freeze this, chill it until the icing is firm before wrapping; then thaw overnight or for several hours in the refrigerator before unwrapping. Before serving the top may be covered with small chocolate shavings which may, if you wish, be coated with a sprinkling of dry powdered sweetened or unsweetened cocoa.