Cream the butter and sugar. Add the eggs, one at a time. Add the sour cream and vanilla. Beat until well blended. Sift together the dry ingredients. I usually just blend them instead of sifting. Add them to the creamed mixture. Mix well . Spoon about half the batter into a greased 25 cm tube pan. Sprinkle batter with Chocolate Chips. I use enough to ALMOST cover the batter. Spoon the rest of the batter over the Chocolate Chips. Sprinkle with remaining Chips and Cinnamon sugar. Bake at 180ºC F for 40-45 minutes or until cake tester comes out clean. ----