Preheat the oven to 375 degrees F (190 degrees C).
Spread 1/3oz of butter on the bottom of the 9" baking pan (I used a round silicone form).
Combine 1 1/2 cup of fresh cranberries, 1/4 cup of sugar, and 1 cup of nuts (hazelnuts are the best :) ) Spread these ingredients into a single layer.
For batter:
Mix 3 eggs, 1/2 cup of sugar, 2/3 cups of flour, 1 1/2 tsp of baking powder, 4 Tbsp of sour cream, 1 tsp of vanilla.
Pour the batter onto the baking pan covering the berries with nuts.
Bake for 30-35 minutes or until it is golden brown.
Cool pie in pan for 5 minutes. Place serving plate over pie, and carefully flip to invert.
Allow to cool for 1 hour.