Cream butter and add sugar, a little at a time. Cream well; add eggs. Sift flour, salt, soda and cocoa together 3 times. Add coffee with flour mixture to batter, alternating. Then add vinegar and vanilla. Bake in 9-inch layer pan 20 to 35 minutes in 350 degrees oven or in loaf pan about 30 to 40 minutes in 350 degrees oven. ----