1 stick (1/2 c.) butter
1/2 c. vegetable oil
2 squares unsweetened chocolate or 4 tbsp. unsweetened cocoa
1 c. water
2 c. unsifted all-purpose flour
1 tsp. baking soda
1 3/4 c. sugar
1/2 c. sour milk (place 1/2 tsp. vinegar in 1/2 c. milk)
2 eggs, beaten
3/4 tsp. cinnamon
1 tsp. vanilla extract

Preheat oven to 350 degrees. Combine butter, oil, chocolate and water in a saucepan and heat until chocolate is melted.

Combine flour, baking soda, sugar, milk, eggs, cinnamon and vanilla in large bowl; then combine first mixture. Pour into a greased 12x18 inch cake pan. Bake 20 to 25 minutes or until cake tests done. Bake on middle rack.

Five minutes before cake is done, prepare:

MEXICAN CHOCOLATE ICING:

1 stick butter
2 squares unsweetened chocolate
6 tbsp. milk
1 (1 lb.) pkg. confectioners' sugar
1 tsp. vanilla extract
1/2 c. chopped pecans

Combine butter, chocolate and milk in a saucepan and heat until bubbles form around the edge. Remove from heat, add confectioners' sugar, vanilla and pecans; beat. Ice cake while still warm. Frosting is not stiff.