I've never made pink champagne cake or heard of it until now...but it sounds delish. I did a quick search on Google and came up with these sites.
This one looks VERY simple and lists the icing to match.
This one has the recipe for bavarian cream
Found this one on Cooksrecipe.com
Pink Champagne Cake
2 3/4 cups sifted all-purpose flour
1 tablespoon baking powder
1 teaspoon salt
2/3 cup vegetable shortening
1 1/2 cups granulated sugar
3/4 cup champagne
6 large egg whites
Preheat oven to 350*F (175*C). Grease and flour 2 (9-inch) round cake pans; set aside.
Whisk together the flour with the baking powder and salt. Set aside.
In a large mixing bowl, cream shortening and 1 cup sugar until light and fluffy with an electric mixer. Beat in flour mixture and champagne alternately, beating until batter is smooth; set aside.
In another mixing bowl, beat egg whites until stiff. Gradually beat in remaining 1/2 cup sugar, continuing beating until meringue forms stiff peaks. Fold about half of the meringue into the cake batter, mixing gently but thoroughly. Gently fold in remaining meringue.
Pour batter into prepared cake pans and bake for 20 to 25 minutes or until tested done when a wooden pick inserted in center comes out clean. Cool cakes in pan on wire rack for 10 minutes. Remove cakes from pans and cool completely on wire racks.
Spread Coconut Filling on to the bottom cake layer.
Top with remaining cake layer and frost sides and top with the Fondant Frosting.
Makes 10 to 12 servings.
This recipe also has a recipe for a coconut marshmellow filling.