Beat first 6 ingredients and 1/2 cup sour cream in large bowl with mixer until blended. Stir in apples.
Pour into greased and floured 10-inch tube pan or 12-cup fluted tube pan.
Bake 1 hour to 1 hour 5 min. or until toothpick inserted near center comes out clean. Cool cake in pan 15 min. Loosen cake from sides of pan with knife. Invert cake onto wire rack; gently remove pan. Cool cake completely.
Whisk sugar, 1 tsp. water and remaining sour cream until blended; drizzle over cake.