Stir flour, baking powder and baking soda until blended. Beat granulated sugar, butter and vanilla in large bowl with mixer until light and fluffy. Add eggs, 1 at a time, beating well after each addition. Beat in flour mixture alternately with sour cream.
Combine nuts, brown sugar and cinnamon; spoon half into greased and floured 12-cup fluted tube pan or 10-inch tube pan; top with half the cake batter. Repeat layers.
Bake 45 to 50 min. or until toothpick inserted near center comes out clean. Cool cake in pan 10 min. Loosen cake from sides of pan with knife. Invert cake onto wire rack; gently remove pan. Cool cake completely.