Cream 1 cup sugar, lemon rind, and egg yolks until the mixture is light and fluffy.
Stir in the almonds and cinnamon.
Beat the egg whites until they are stiff, but not dry.
Stir a few tablespoons of the egg white into the almond mixture, then fold in the rest of the egg whites.
Pour into 2 greased 8-inch layer pans and bake at 350°F for 45 minutes or until the cakes are well browned. Cool briefly, then remove the cakes from the pans.
To make topping, whip 1/2 pint of whipping cream, 1/4 teaspoon sugar and 1 teaspoon very strong brandy (optional) until stiff.
Spread between the cake layers, then coat the top and sides of the cake. Garnish with chopped almonds.
An alternative is to use the filling inside, then sprinkle the top with powdered sugar after placing a 4-inch Cross of Santiago in the center. The end result is a brown cross on a field of powdered sugar.