4 large red potatoes (2 pounds) |
2 medium-size sweet potatoes (1 1/2 pounds) |
1/4 cup butter or margarine |
1/2 cup milk |
1/4 cup sour cream |
1/4 cup freshly grated parmesan cheese |
1 tablespoon prepared horseradish |
1/4 teaspoon salt |
1/4 teaspoon pepper |
1/4 teaspoon ground cinnamon |
1/8 teaspoon ground nutmeg |
butter or margarine (optional) |