For classic buttercream frosting, combine 3 cups of confectioner's sugar and 1 cup of butter with a mixer set to low, and mix for an additional three minutes on medium speed. Add 1 teaspoon of vanilla and 1 to 2 tablespoons of whipping cream and mix for one additional minute.
To make chocolate buttercream frosting, cream 1/2 cup shortening and 1/2 cup softened butter together, and add 3/4 cup cocoa and 1 teaspoon vanilla extract to the mixture. Set the mixer to medium speed and slowly add 4 cups of confectioner's sugar while mixing continuously. Pour in 3 to 4 tablespoons of milk to thin the frosting and beat until the frosting is fluffy. To make mocha frosting, replace the milk with strongly brewed coffee.
Use fresh strawberries to make strawberry buttercream frosting. Beat 1 cup of butter until the butter is fluffy, add 32 ounces of sifted confectioner's sugar and 1 cup of fresh, chopped strawberries, and mix the ingredients together on low speed until well-combined. Add additional strawberries to the frosting if it is too thick.
Tinted frosting is also an option. To color classic buttercream frosting, dip a toothpick in gel food coloring and then swirl the toothpick in the frosting. When making red, black or brown frosting, use up to 1 teaspoon of coloring per cup of icing to reach the desired color.