Preheat the oven to 350°F. Lightly grease a 9x5x3-inch loaf pan. Set aside. Using an electric mixer, beat together the sour cream, sugar, eggs, and vanilla on low speed until well blended.
Fold in the apples and 3/4 cup of the nuts into the batter. Transfer the batter into the greased loaf pan. Sprinkle the rest of the nuts on top and then press them lightly into the batter.
Bake for about 50-60 minutes or until a toothpick inserted into the center comes out clean.
Cool in the loaf pan for about 20-30 minutes and then transfer to a wire rack.