Step 1

Preheat the oven to 350 degrees F (175 degrees C). Generously grease a 9 inch springform pan. Wrap aluminum foil around the outside of the bottom to prevent leaking.

Step 2

Melt the butter in a saucepan over medium heat. Stir in 1 1/2 cups of white sugar, water and cinnamon until sugar has dissolved. Bring to a boil and then add the cranberries. Stir to coat with the sauce, then pour into the prepared pan.

Step 3

Sift together the flour, baking soda and salt; set aside. In a medium bowl, beat the remaining 6 tablespoons of butter with 1/2 cup white sugar and brown sugar until light and fluffy. Mix in the eggs one at a time, beating well after each addition. Stir in vanilla and sour cream. Mix in the dry ingredients. Pour the batter over the cranberries in the pan.

Step 4

Bake for about 50 minutes in the preheated oven, or until a knife inserted into the center comes out clean. Cool on a rack for 10 minutes, then run a knife around the outer edge. Invert onto a serving plate and remove the springform pan.