Cornstarch Frosting is a recipe is from Stephanie. She sent it to me after reading my review of Quick Chocolate Cupcakes with a flour based frosting, a mixture of flour and milk that is cooked and then whipped into a mixture of butter and granulated sugar. The texture, after you beat it enough so that the sugar dissolves, is supposed to be similar to a rich buttercream and less sweet than typical powdered sugar icing. Update: I recently learned this one is also known as Ermine frosting.
Cornstarch Frosting or Ermine Frosting
This is similar to the flour based icing, but calls for cornstarch. Stephanie's recipe was passed down verbally by her father, and is the one she has been using on cupcakes for years. To me, it seems a little smoother and fresher tasting than the icing made with flour -- slick, buttery, and deeply vanilla. I still think I like powdered sugar frosting best, but if you’re looking for a less sweet icing or you just happen to be out of powdered sugar, this is a good alternative.
As for the "Ermine" name, I'm still reading up on that but I suppose its smooth texture can be comparable to silky to the fur on an ermine or a robe made of ermine?
Cornstarch Frosting aka Ermine Frosting
¾ cup milk (whole, reduced fat and skim all work) 180 grams
2 tablespoons cornstarch (16-18 grams)
¾ cup sugar (150 grams)
¾ cup (1 ½ sticks) butter -- salted (170 grams), softened but cool
½ teaspoon vanilla
Combine cold milk and cornstarch in a saucepan and whisk until blended. Set over medium heat and whisk until thick. Let cool.
With an electric mixer, cream together sugar and softened butter until light and fluffy.
Add the cooled milk mixture and the vanilla, then whip until mixture resembles whipped cream.
Makes enough frosting for 24 cupcakes.