Sift flour, baking powder & salt. Cream shortening. Slowly beat in sugar. Add egg yolds & vanilla. Add cocoa, then flour mixture alternately with milk. Fold in stiffly beaten egg whites. Pour in 2 greased 23 cm layer cake tins. Bake 25 minutes in 190ºC oven. FROSTING:Combine 2 egg whites, unbeaten with 1.5 cups sugar, finely sifted. Add 5 tablespoons. cold water, a few rains salt and half tsp. Cream of Tarter in top of double boiler. Stir until sugar is dissolved. Place over briskly boiling water. Beat with egg beater until stiff enough to stand in peaks, about 6-10 minutes. Add 1 tsp. vanilla and beat until thick enough to spread while frosting is cooling. Keep sides of double boiler scraped down with spatula. ----