Heat oven to 180ºC . Butter bottom and sides of two 23 cm round baking pans. Line bottoms with wax paper; butter paper. In small saucepan, melt butter; remove from heat. Stir in cocoa, blending well; cool slightly. In large mixer bowl, beat eggs until foamy; add salt and vanilla. Gradually add sugar, beating well. Add cooled chocolate mixture; blend thoroughly. Fold in flour. Stir in pecans. Pour batter into prepared pans. Bake 20 to 25 minutes or until wooden pick inserted in center comes out clean. Do not overbake. Cool 5 minutes; remove from pans. Carefully peel off paper. Cool completely. Spread Creamy Coffee Filling between layers, over top and sides of cake. Garnish with Chocolate curls, if desired. Refrigerate 1 hour or longer before serving.
YIELD: 10 to dozen servings CREAMY COFFEE FILLING: In small mixer bowl, combine all ingredients; stir until coffee is almost dissolved. Beat until stiff.
YIELD: about 3 cups filling MAKE AHEAD DIRECTIONS: Cooled cake may be wrapped and frozen up to 4 weeks; thaw, wrapped, before filling and frosting.