Cream butter with sugar
Add 2 beaten eggs and mix enough to blend
Sift together the flour, baking powder, baking soda, and salt
Mix vanilla into sour cream
alternate adding dry ingredients and sour cream to creamed mixture. Mix enough to just blend all ingredients.
In a separate small bowl, combine chopped walnuts, sugar, and cinnamon.
Pour half of the batter into a greased 9 inch tube pan.
Sprinkle a little more than half of the walnut/sugar/cinnamon mixture onto the batter.
Pour the rest of the batter on top.
Top with the remaining walnut/sugar/cinnamon mixture.
Bake at 350 degrees for 45 minutes.
Allow to cool then remove from the pan.