This is the tastiest sour cream coffee cake recipe in the world owing, I think, to the brown sugar in the batter. It comes out best in a 9 tube or bundt cake pan, but I made it for years in a regular 10 tube pan. It was a little flat, but still yummy.
Topping
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¼ cup brown sugar, firmly packed
1 tsp cinnamon
¼ cup chopped nuts or chopped chocolate chips
Combine the topping ingredients and set aside.
½ cup butter, softened
½ cup brown sugar, firmly packed
1 cup white sugar
2 eggs
2 cups flour
1 tsp baking powder
1 tsp baking soda
dash of salt
1 cup sour cream
Oven 350 9 or 10 tube or bundt pan
In a large mixing bowl, cream the butter and sugars. Add the eggs one at a time, beating well after each. Sift together the dry ingredients and add alternately with the sour cream, beginning and ending with the flour mixture. Put one-third of batter in greased and floured pan. Sprinkle with half the topping mixture. Add another third of the batter, then the rest of the topping. Top with the rest of the batter. Bake at 350 for 45 to 50 minutes. Let cool in pan about 15 minutes, then turn out on rack to cool.