Cream the butter and sugar. Add vanilla. Fold in sour cream. Add eggs, 1 at a time; beat well. Sift dry ingredients together; fold into the mixture. Prepare before hand: 

1/2 cup of sugar
2 teaspoons of cinnamon
1 can coconut

Spread half the batter in pan; sprinkle half the cinnamon mixture over batter; cut through with a knife. Top with the remaining batter and then remaining cinnamon mixture. Bake at 350ºF. for 35 to 45 minutes.  *Reduce to 325ºF. if using glass pan. Recipe calls for 7 x 11 inch pan - I use 9 x 13 inch pan and adjust cooking time. Serves 12.