Sour Cream Coffee Cake

1 1/2 Stick Margarine
2 cups Sugar
2 eggs
2 cups All Purpose Flour
1 tsp Vanilla
1 tsp Baking Powder
1/2 tsp salt
1 cup Sour Cream

Sugar Nut Mixture
3 tbsp brown sugar
1 tsp Cinnamon
1/2 cup chopped nuts

Cream margarine and sugar. Add eggs, then vanilla. Sift flour, baking powder and salt together and add alternately with sour cream. Place 1/2 of the batter into a greased, floured pan. Sprinkle with sugar nut mixture; add the remainder of batter and bake at 350 for 1 hour and 20 minutes.