1preheat oven to 325°. Spray a 15 cup Bundt pan with nonstick baking spray with flour. Set aside. In a large bowl, beat butter and medium speed with a mixer until creamy. Gradually add sugar, beating until fluffy. Add eggs, one at a time, beating well after each addition. In a large bowl, sift together flour, baking soda, and salt. Add flour mixture to butter mixture, alternately with 1 cup sour cream, beginning and ending with flour mixture. Add 1 teaspoon lemon zest, lemon juice, 1 teaspoon orange zest, orange juice, 1 teaspoon lime zest, and vanilla. Stir to mix. Pour batter into prepared pan.
2Bake until a wooden pick inserted in the center of the cake comes out clean, one hour 15 minutes to 1 hour 30 minutes. Cover cake loosely with foil if it begins to brown
3Let cool in pan for 10 minutes. Remove from pan and let cool completely on wire rack.
4In a medium bowl, whisk together remaining 1/2 cup sour cream, powdered sugar, and lime juice. Spoon over cooled cake. Sprinkle with remaining 2 teaspoons lemon zest, remaining 2 teaspoons orange zest, and remaining 2 teaspoons lime zest. Refrigerate cake until ready to serve. Makes one 10 inch cake.