Preheat oven to 350. Spray a 10 inch cake pan generously with non stick spray. Set prepared pan on a foil lined sheet pan. Set aside.
In a large bowl beat egg whites until they hold stiff peaks
In another large bowl combine egg yolks,with sour cream, sugar, vanilla, ground cinnamon, pumpkin pie spice and salt, best until light and fluffy. Best in melted cinnamon chips until well combined.
Add a third of the egg whites to the yolk mixture and fold in to lighten. Add another third and fold in and then the final third and gently fold until combined..Pour into prepared pan. Sprinkle top with the.1/4 cup additional cinnamon chips if using
Bake for about 30 minutes just until a wooden pick comes out clean. The cake will rise quite high but will deflate some while cooling. Cool.in pan 15 minutes then run a small sharp knife around edges to release any parts that stick and cool another 30 minutes before removing from pan
Serve with Whipped Cream and sprinkle with Cinnamon Sugar
https://cookpad.com/us/recipes/343417-stabilized-whipped-cream-for-frosting-topping-and-dipping
https://cookpad.com/us/recipes/350614-cinnamon-sugar
