Ermine frosting is an ultra creamy frosting that's made with a mixture of boiled milk, flour, and sugar mixed with butter. It's less sweet than traditional buttercream, but its whipped texture and rich flavor make it the ideal choice for red velvet cakes and cupcakes!
Add the granulated sugar, flour, and salt to a medium saucepan and whisk until well combined. Slowly pour in the milk, whisking constantly until the mixture is smooth.
Place the saucepan over medium heat and cook, stirring often, until you have a thick and smooth paste (almost like pudding). I suggest using a rubber spatula to scrape around the bottom and sides of the pan several times as it’s cooking. This step can take up to 15 minutes, so be patient.
Remove from the heat and transfer the mixture to a large heat-safe bowl. Place a piece of plastic wrap directly on the surface to prevent a skin from forming on the top and let it cool completely to room temperature. If needed, you can refrigerate the mixture to speed up the process. Just make sure it’s at about room temperature and not too cold when you add it to the butter.
Add the softened butter to the bowl of a stand mixer fitted with the paddle attachment, or a large mixing bowl using a handheld mixer. Beat the butter for 4 to 5 minutes until it's light in color and fluffy.
With the mixer on medium speed, add the cooked flour mixture one heaping tablespoon at a time, waiting until fully combined to add the next spoonful.
Once all of the cooked flour mixture has been added, add the vanilla extract and mix for 2 to 3 more minutes on medium speed or until the frosting has thickened and is smooth and creamy. Once the mixture is ready, it should resemble whipped cream. If needed, use a rubber spatula to work out any air bubbles.
Notes
Storage Instructions: Frosting may be stored in an airtight container in the fridge for 3 to 4 days. Bring to room temperature and mix well before using.Freezing Instructions: Frosting may be frozen for 2 to 3 months. Thaw overnight in the refrigerator, bring to room temperature, and mix well before using the frosting.