Partially melt chocolate over hot water. Remove and stir rapidly until entirel y melted. Cool. Cream sugar and oleo. Add eggs, vanilla and buttermilk. Th en flour mixture. Stir in chocolate until blended.
Bake at 300-325 degrees for 1 1/2 hours in greased and floured bundt pan. Remo ve from pan and place under tight cover until thoroughly cold.