The texture of this frosting is similar to whipped cream...luscious.
Fluffy Vanilla Frosting
5 Tablespoons flour
1 cup milk
1 teaspoon vanilla extract
1/2 cup butter, softened & 1/2 cup shortening
1 cup granulated sugar (not Powdered Sugar)
In a small or medium saucepan, add milk and whisk in flour over medium-low heat. Whisk continually until mixture is very thick...almost as thick as brownie batter; It must be thick, or the frosting will not set up properly.
Remove pan from heat. Set aside to cool completely on counter; I place on cool, wet dishtowel.
Place plastic wrap directly ON top of mixture while cooling. For the next step, the milk/flour mixture must not be warm AT ALL, but if you cool mixture in refrigerator, then bring back to room temperature before proceeding. Once mixture has cooled, add in vanilla extract.
In large mixing bowl, cream together the butter, shortening, and granulated sugar on low for 2 minutes, then on medium-high speed for 6 minutes. Add in the cooled milk/flour mixture and continue beating on medium-high for 8 minutes until resembles whipped cream. Frost cake/cupcakes and store in refrigerator (for firmer texture) or at room temperature (for softer texture).