Heat oven to 350. Spary a 9x13 pan with spray. In a large bowl, combine flour, 1 1/2 cups sugar, baking powder, baking soda, salt, sour cream, butter, vanilla and eggs. Blend at low speed of electric mixer for 3 minutes.
Pour one-half of the batter into prepared pan. Combine the remaining 1/2 cup sugar and cinnamon. Sprinkle one-half of sugar mixture and one-half chocolate chips over batter. Repeat with remaining batter, sugar mixture and chocolate chips.
Bake 35 to 40 minutes or until a wooden toothpick comes out clean. Remove from oven and cool.