Preheat oven to 350 degrees F (175 degrees C). Grease thoroughly a fluted 2 quart ring mold, and dust lightly with flour.
Sift pastry flour, salt, and baking powder together.
In a large bowl, cream shortening well. Gradually blend in 1 1/2 cups sugar, eggs, vanilla, and 3 tablespoons cognac; beat until light and fluffy. Gently blend sifted ingredients alternately with the milk and cream into the creamed mixture. Pour batter into ring mold.
Bake for 45 to 50 minutes, or until cake springs back when lightly touched. Remove from pan, and allow to cool.
In a clean, cold bowl, beat the 2 cups whipping cream until peaks form. Stir in 1/4 cup sugar and coffee powder. Frost the cake with whipped cream. When serving, drizzle cake with a few drops of cognac.