Flour Frosting (a.k.a. Ermine Frosting) Recipe

An easy, old-fashioned frosting as light and silky as whipped cream.

By
Stella Parks
Stella Parks
Editor Emeritus
Stella Parks is a CIA-trained baking nerd and pastry wizard, dubbed one of America's Best New Pastry Chefs by Food & Wine. She was the pastry editor at Serious Eats from 2016 to 2019.
Learn about Serious Eats' Editorial Process
Updated May 17, 2023
A slice of Neopolitan cake being cut from the cake.

Serious Eats / Vicky Wasik

Why It Works

  • Cooking the flour alone in milk allows it to fully cook, activating its thickening power and eliminating any raw or starchy flavor.
  • Adding sugar to the finished flour paste ensures it melts completely but doesn't interfere with the cooking process.
  • A paddle attachment works best to ensure the frosting is smooth, while the whisk attachment helps it fully aerate.

While it may sit on a relatively obscure branch of the buttercream family tree, flour frosting is among the easiest to prepare—no eggs or meringue, candy thermometers, or powdered sugar in sight.

What Is Flour Frosting?

Flour frosting is a starch-thickened, milk-based frosting made with granulated sugar, giving it some broad similarities to German buttercream in terms of both flavor and technique. But flour frosting is eggless, so there's no custardy flavor or yolk-y color—only the clean taste of fresh milk and butterfat (a combination that, unsurprisingly, tastes much like whipped cream).

Flour frosting feels as soft, fluffy, and luxurious as a billowing fur coat, which is perhaps how it came to be called "ermine frosting" in some parts of the country, where it's the traditional finish for a red velvet cake.

Overhead close-up of a cake frosted with flour frosting.

Serious Eats / Vicky Wasik

Personally, I'm fond of letting its simplicity provide an element of contrast with boldly flavored cakes, like chocolate and strawberry, but its creamy richness can just as easily highlight the primary flavors of a classic vanilla cake.

Virtually all recipes approach flour frosting in one of two ways. Some will have you cook the flour and milk together until thick, then whip the cooled paste with granulated sugar and butter. Others call for cooking the flour and milk together with the sugar, then whipping the cooled paste with butter.

The former yields the best flavor and body, but frosting made this way often contains a trace of grit from undissolved sugar crystals. The latter results in the silkiest texture, but because sugar alters the boiling point of milk, the flour isn't as thoroughly cooked, giving the frosting a starchy aftertaste and comparatively loose body.

Happily, I've found that it's easy enough to split the difference in technique, for a flavorful, full-bodied frosting free of any grit or starchiness. It starts with all the same ingredients: flour, sugar, and milk, plus a little salt.

Ingredients for flour frosting: flour, sugar, milk, and salt.

Serious Eats / Vicky Wasik

Making the Frosting's Base

I start by whisking the flour and milk until smooth, then boiling them together. This ensures the flour is fully cooked, eliminating its starchy flavor and forming a thick, roux-like paste.

When the flour-milk paste is fully cooked, I shut off the heat and add the sugar so it can dissolve into the warm mixture. Because this step liquefies the sugar, the mixture will seem runny and thin, but rest assured that the flour's thickening power has not been compromised.

I set the mixture aside and allow it to cool to about 70°F (21°C). Meanwhile, I warm the butter until it's pliable and soft, but still cool to the touch, about 65°F (18°C). This can be done passively over time on the counter, or with a few controlled bursts in a microwave.

Either way, it's less about achieving some laser-precise temperature than it is about quantifying a more useful ballpark figure than "room temperature." The idea is to have butter that is neither rock-hard from the fridge nor squishy from sitting out all day.

Using a stand mixer fitted with a paddle attachment, beat the butter until it's creamy, light, and soft, but not loose. In my kitchen, this takes about five minutes.

Butter before and after creaming.

Serious Eats / Vicky Wasik

As with any recipe, the listed time is an approximation, not a goal. Times are meant to contextualize, not constrain, a physical process. The only goal is to achieve the visual and textural cues described.

Once the butter is soft and light, begin adding the cooled milk paste, a little at a time.

A spatula holding the milk paste and butter mixture being whipped in a stand mixer.

Serious Eats / Vicky Wasik

Continue beating the frosting until it's homogeneous, pausing to scrape the bowl and beater as needed. When the frosting looks perfectly smooth, switch to a whisk attachment, and whip until it's airy and light.

Perfecting the Texture

As with any buttercream, the final stage of whipping will likely require some adjustment to reach the appropriate temperature. A soft, loose buttercream will need to be chilled, while a dense, heavy, greasy, or curdled buttercream will need to be warmed.

This is normal! However precise a recipe may be in terms of target temperatures (for both the ingredients and the finished product), the ideal working temperature of a buttercream can vary from batch to batch, depending on environmental conditions and the time of year, as well as variations in equipment and ingredients.

So, rather than rely on a thermometer alone, evaluate the texture and consistency of the frosting. If it's heavy and dense, if it has a greasy texture, or if it seems curdled, it will need to be warmed and re-whipped. If it's too soft or loose to hang from a spoon without dropping, it will need to be cooled and re-whipped. These are routine adjustments, not a sign of failure. (For more specifics, check out my buttercream troubleshooting guide—though it was originally designed with Swiss buttercream in mind, these methods will work for any buttercream.)

Adding vanilla extract to ermine frosting in the bowl of a stand mixer.

Serious Eats / Vicky Wasik

When the temperature and texture of the frosting have been properly adjusted, it can be seasoned to taste with additional salt, as well as vanilla extract (or whatever other extract you prefer).

Flour frosting may not be as sturdy as a German buttercream or as airy as a Swiss one, but it's a wonderful alternative when circumstances, or dietary considerations, rule out the use of eggs.

Neapolitan cake slices

Serious Eats / Vicky Wasik

Likewise, ermine may not be as quick and easy as a traditional American buttercream, but it avoids the use of powdered sugar. What's more, flour frosting contains less sugar than any other buttercream style, so it can bring balance to sweeter cakes or those meant to be served à la mode.

Thanks to these attributes, along with its uniquely cream-like flavor, flour frosting has more than earned its place in my recipe repertoire, and I hope you'll find it just as useful.

May 2019

Recipe Details

Flour Frosting (a.k.a. Ermine Frosting) Recipe

Prep 15 mins
Cook 5 mins
Active 15 mins
Total 20 mins
Serves 16 servings
Makes 2 cups
Cook Mode (Keep screen awake)

Ingredients

  • 1 ounce all-purpose flour (about 3 tablespoons plus 2 teaspoons; 28g)

  • 6 ounces milkany percentage will do (about 3/4 cup; 170g)

  • 3 1/4 ounces (96g) plain or toasted sugar (see note)

  • Heaping 1/4 teaspoon (1.5g) Diamond Crystal kosher salt, plus more to taste; for table salt, use about half as much by volume or the same weight

  • 6 ounces (160g) unsalted butter, softened to about 65°F (18°C)

  • 1/4 ounce vanilla extract (1 1/2 teaspoons; 7g), plus more to taste

Directions

  1. In a 10-inch skillet or 3-quart saucier, whisk together flour and milk. Place over medium heat, whisking constantly, and cook until thick and pudding-like, about 2 minutes. Off heat, add sugar and salt. Whisk until sugar has dissolved and the "pudding" is homogeneous but thin. Scrape mixture into a wide, shallow dish, such as a pie plate, and cool to approximately 70°F (21°C).

    A five-image collage: Combining flour and milk, whisking until homogeneous and adding sugar to the milk paste, then transferring the paste to a plate to cool.

    Serious Eats / Vicky Wasik

  2. Place butter in the bowl of a stand mixer fitted with a paddle attachment. Mix on low until the butter looks smooth, then increase speed to medium and beat until soft and light, about 5 minutes. Begin adding the cooled pudding, a few tablespoons at a time. Once it's fully incorporated, pause to scrape bowl and beater with a flexible spatula, then resume beating until perfectly smooth.

    Butter in a stand mixer after being beaten until smooth.

    Serious Eats / Vicky Wasik

  3. Switch to the whisk attachment and add vanilla. Whip on low to combine, then increase speed to medium-high and continue whipping until silky-smooth and soft, with a light, melt-in-your-mouth consistency, about 3 minutes more, or to a working temperature of approximately 75°F (24°C). Season to taste with additional salt and/or vanilla as needed. Use immediately, or consult the troubleshooting guide below to address any textural inconsistencies.

    Flour frosting retaining its peak on a whisk attachment.

    Serious Eats / Vicky Wasik

  4. Troubleshooting: If the frosting feels dense, stiff, greasy, or curdled, it is likely too cold; to warm, briefly set over a pan of steaming water, just until you see the edges melting slightly, then re-whip. If the frosting feels soft and loose, it is likely too warm. Pop it in the fridge for 15 minutes to cool, then re-whip.

Special Equipment

3-quart saucier or 10-inch skillet, balloon whisk, stand mixer, flexible spatula

Notes

This recipe will work with any type of sugar, including brown sugar and semi-refined styles, such as turbinado or Sugar In The Raw.

Make-Ahead and Storage

In a quart-sized, heavy-duty zip-top bag, the frosting can be refrigerated for one week or frozen for several months. Before use, thaw to about 70°F (21°C) and re-whip until smooth, consulting the troubleshooting guide above as needed to address textural concerns.

Read More

Nutrition Facts (per serving)
113Calories
9gFat
8gCarbs
1gProtein
×
Nutrition Facts
Servings: 16
Amount per serving
Calories113
% Daily Value*
Total Fat 9g11%
Saturated Fat 6g28%
Cholesterol 24mg8%
Sodium 43mg2%
Total Carbohydrate 8g3%
Dietary Fiber 0g0%
Total Sugars 7g
Protein 1g
Vitamin C 0mg0%
Calcium 17mg1%
Iron 0mg1%
Potassium 21mg0%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

More Serious Eats Recipes