SugarFreeMom.com's recipe for sugar-free vanilla buttercream frosting is a simple recipe that uses a combination of Stevia and erythritol to replace sugar. Splenda.com also offers several recipes for sugar-free icing, including rich chocolate frosting.
To make Sugar Free Mom's sugar-free vanilla buttercream frosting, place 1/2 cup of room-temperature butter, 1 1/4 cup powdered erythritol, 1 teaspoon of vanilla extract, 1/2 or 1 teaspoon of liquid Stevia and 1 tablespoon of milk in a mixing bowl. Mix the ingredients together until the icing reaches the desired consistency. If a thicker icing is desired, omit the milk. If making a thin glaze, additional milk may be used. Any unused frosting may be frozen for up to three months.
For Splenda's rich chocolate frosting, sprinkle 1 0.25-ounce packet of gelatin over 3/4 cup of cold milk in a saucepan. Let the mixture stand for one minute, then cook over low heat until the gelatin dissolves. Add 6 ounces of chopped semi-sweet chocolate and continue cooking over low heat until the chocolate melts.
Let the mixture stand for ten minutes. In a bowl, combine 1/2 cup Splenda, 1/4 teaspoon salt and 3 tablespoons chocolate syrup. Add the Splenda to the milk mixture and cook over low heat for two minutes. Remove from heat, add 1/4 teaspoon vanilla extract and let stand for 20 minutes. Beat at high speed for five to eight minutes until fluffy.