½ cup raw coconut chips or flaked coconut, lightly toasted
Thinly sliced Key lime
Let butter and eggs stand at room temperature for 30 minutes. Grease and flour a 10-inch tube pan; set aside. Preheat oven to 350°.
In a large mixing bowl, beat butter, baking powder and salt with an electric mixer on medium to high speed for 30 seconds. Gradually add sugar, about 1/4 cup at a time, beating on medium speed until well combined. Scrape sides of bowl; beat for 2 minutes more. Add eggs one at a time, beating well after each addition. Beat in vanilla. In a small bowl, combine milk, cream of coconut, lime zest and lime juice. Alternately add flour mixture and milk mixture to butter mixture, beating on low speed after each addition just until combined. Spoon batter evenly into the prepared pan.
Bake for 40 minutes or until a wooden toothpick inserted near center comes out clean. Cool cake in pan on a wire rack for 15 minutes. Remove cake from pan; cool on wire rack. (At this point, the unfrosted cake can be stored in an airtight container up to 2 days at room temperature.)
To serve, place cooled cake on a serving plate. Generously frost with Marshmallow Frosting. Sprinkle with coconut chips and lime slices. Serve cake the same day it is frosted, preferably soon after frosting it.