2 cups all-purpose unbleached flour
1 tsp baking powder
1 tsp baking soda
1/4 lb (1 stick) butter, softened
1-1/3 cup granulated sugar, divided
2 large eggs
1 tsp vanilla extract
1 cup (8 oz) sour cream
1 Tbsp cinnamon
Preheat oven to 350°F. (Note: if using a ceramic pan, do not preheat the oven.) Spray the inside of a small (5-cup) Bundt pan or loaf pan with baking spray, and set aside. A tip Lorna shared: if you're using a Bundt pan, roll a small piece of parchment paper, an inch or so taller than the pan; place the pan on a sheet pan, and insert the parchment paper in the hole. If the cake rises above the top of the pan, it won't slide down in the center.
In a mixing bowl, stir together the flour, baking powder and baking soda.
In the bowl of a Kitchenaid-type stand mixer, cream together the butter, 1 cup of sugar, and the eggs, until the eggs turn light yellow. Stir in the vanilla. Add to the egg mixture, alternating, the dry ingredients and sour cream.
Pour half of the batter into the prepared pan, and spread evenly.
In a small bowl, stir together the remaining 1/3 cup of sugar and the cinnamon. Sprinkle this over the batter in the pan, and top with the remaining batter.
Bake at 350F for 45 minutes (if using a ceramic pan, place the pan in a cold oven, set to 350F, and bake for 60 minutes), or until a tester comes out clean.
Set the pan on a wire rack to cool for 15 minutes, then invert the pan and remove the cake. Let it cool completely. Serve, or wrap and freeze.