Red,White and Blue Ambrosia

1. Combine the heavy cream and confectioners' sugar in a large bowl. Whip with an electric mixer until thick but not grainy. Mix in sour cream.
2. Use a rubber spatula to fold in the flaked coconut, pineapple, strawberries, blueberries and marshmallows until everything is evenly distributed. Cover and chill for at least 4 hours before serving. It tastes best if chilled overnight.