Desserts

There are frostings you make because a cake needs covering. And then there are frostings like this Vegan Ermine Frosting — the kind that pipes onto a cake in the most impossibly silky, light, cloud-like swirls imaginable, that tastes so subtly sweet and so deeply of real vanilla that people who have spent their entire baking lives using powdered sugar buttercream take one bite and immediately ask what this frosting is and why they have never made it before. This is that frosting. The one that changes how you think about frosting permanently. The one that makes every cake it touches taste more sophisticated and more genuinely delicious than it did with any buttercream you have made before.

Ermine frosting — also known as flour frosting, boiled milk frosting, or heritage frosting — is the oldest style of American cake frosting, predating the powdered sugar buttercream that became standard in the mid-twentieth century. It is made by cooking flour and plant milk into a thick, silky paste called a roux, then beating that cooled roux into whipped vegan butter until the two emulsify into a frosting of extraordinary lightness, stability, and delicate sweetness that is categorically different from any powdered-sugar-based frosting.

What makes ermine frosting so outstanding is its texture — lighter than cream cheese frosting, silkier than Swiss meringue buttercream, less sweet than any powdered sugar buttercream, and more stable than whipped cream. It pipes beautifully, holds at room temperature longer than most frostings, and — critically — tastes of butter and vanilla rather than of sugar, making the cake beneath it the star rather than the frosting.

This recipe is 100% vegan, ready in about 30 minutes including cooling time, and absolutely the most versatile, most elegant, and most surprisingly delicious frosting in the entire plant-based baking repertoire.

Recipe Information

Ingredients

For the Flour Paste (Roux)

• ¼ cup (30g) all-purpose flour
• 1 cup (240ml) unsweetened plant milk (oat milk recommended for neutral flavor)
• ½ cup (100g) cane sugar
• Pinch of salt

For the Frosting

• 1 cup (225g) vegan butter, softened to room temperature
• 1½ tsp pure vanilla extract

Optional Flavor Variations

• 1 tbsp cocoa powder whisked into the roux for chocolate ermine frosting
• Zest of 2 lemons added to the roux for lemon ermine frosting
• 1 tbsp instant coffee dissolved in the plant milk for mocha ermine frosting
• 2 tbsp strawberry freeze-dried powder for strawberry ermine frosting

Instructions

1. Make the flour paste. In a small saucepan whisk together the flour, plant milk, sugar, and salt until completely smooth and lump-free before applying any heat. Place over medium heat and cook, whisking continuously without stopping, until the mixture thickens dramatically into a thick, glossy, pudding-like paste that holds its shape when the whisk is lifted — approximately 6–8 minutes. The paste should be thick enough that it briefly holds the whisk trail on the surface.
2. Cool completely. Transfer the paste to a clean bowl and press plastic wrap directly onto the surface to prevent a skin forming. Cool to room temperature — approximately 20 minutes on the counter, or 10 minutes in the refrigerator if you are in a hurry. This step is non-negotiable. Adding warm paste to butter melts the butter and produces a greasy, separated mess rather than a fluffy frosting.
3. Beat the vegan butter. While the paste cools, beat the room-temperature vegan butter in a stand mixer or with a hand mixer on high speed for 3–4 minutes until very pale, fluffy, and almost white in color. The butter must be properly aerated before the paste is added.
4. Add the paste gradually. With the mixer running on medium speed, add the completely cooled paste to the beaten butter one tablespoon at a time, waiting for each addition to be fully incorporated before adding the next. This gradual addition is essential — adding the paste too quickly prevents proper emulsification and produces a curdled, separated frosting.
5. Beat until silky. Once all the paste is incorporated, increase the speed to high and beat for 3–5 minutes until the frosting is extraordinarily light, fluffy, and perfectly smooth with no visible separation. Add the vanilla extract and beat for 60 seconds more. If the frosting looks slightly curdled at any point, continue beating on high — it almost always comes together within a further 2–3 minutes.
6. Use immediately or store. The frosting is ready to pipe or spread immediately, or can be stored as directed below.

Pro Tips

• The paste must be completely, fully, non-negotiably cool before it touches the butter. Even slightly warm paste begins to melt the butter and produces separation that is very difficult to recover from. When in doubt, refrigerate for 5 more minutes.
• The butter must be at room temperature — not cold, not melted, but soft enough to hold a finger indentation without the finger going through. Cold butter will not aerate properly; melted butter will not emulsify with the paste.
• Add the paste very gradually — one tablespoon at a time — and wait for full incorporation before each addition. Rushing this step is the most common cause of curdled ermine frosting.
• If the frosting does curdle or separate, do not panic. Continue beating on high speed for 5–8 minutes — it almost always emulsifies. If it remains separated, briefly warming the bowl over warm water while beating usually resolves the issue.
• Beat for the full 3–5 minutes after all the paste is added — the difference between a frosting beaten for 2 minutes and one beaten for 5 minutes is dramatic in terms of lightness and silkiness.

Why Ermine Frosting Is the Best Frosting You Are Not Making

Ermine frosting was the dominant American cake frosting from the late nineteenth century through the 1940s, appearing in virtually every American home baking cookbook of the era. Its fall from popularity coincides almost exactly with the mass-market availability of commercial powdered sugar in the mid-twentieth century, which made the simpler powdered-sugar-and-butter buttercream faster and easier to produce.

But easier is not better. Powdered sugar buttercream is sweeter, heavier, grainier in texture, and more likely to leave that specific coating-the-mouth-with-sugar sensation that makes some people find heavily frosted cakes overwhelming. Ermine frosting has none of these qualities. It is lighter, less sweet, smoother, more stable, and — to many bakers who encounter it for the first time — simply more delicious.

In the plant-based baking world, ermine frosting has an additional advantage: it eliminates the need for vegan cream cheese (which can vary in quality) or aquafaba (which requires stabilization and can be temperamental), relying only on plant milk and vegan butter — two ingredients that every plant-based baker already has and that perform entirely predictably.

How Ermine Frosting Compares to Other Frostings

Flavor Variations

• Chocolate Ermine Frosting: Whisk 2 tablespoons of cocoa powder into the flour paste mixture before cooking for a deeply chocolatey version that is extraordinary on chocolate or vanilla cake.
• Lemon Ermine Frosting: Add the zest of 2 lemons and a tablespoon of fresh lemon juice to the cooled paste before beating into the butter for a bright, citrusy version.
• Strawberry Ermine Frosting: Add 2 tablespoons of freeze-dried strawberry powder to the cooled paste for a naturally pink, intensely fruity version with no artificial coloring.

Nutritional Highlights (Per Serving — 2 tbsp)

Storage

• Room temperature: Ermine frosting holds at cool room temperature for up to 6 hours — significantly better than most plant-based frostings which soften quickly.
• Refrigerator: Store in an airtight container for up to 5 days. The frosting firms in the refrigerator — re-beat briefly with a mixer to restore the original light, silky texture before using.
• Freezer: Freeze for up to 2 months. Thaw overnight in the refrigerator and re-beat before using.
• Frosted cake: A cake frosted with ermine frosting can be kept at cool room temperature for up to 2 days or refrigerated for up to 5 days.

Frequently Asked Questions

Why did my ermine frosting curdle or separate?

Curdling is almost always caused by paste that was too warm when added to the butter, butter that was too cold, or paste added too quickly. Continue beating on high speed for several minutes — ermine frosting almost always comes together with sustained beating. If it remains separated, place the bowl briefly over warm water while beating.

Can I make ermine frosting without a stand mixer?

Yes — a hand mixer works well. The process takes slightly longer but produces the same result. A whisk by hand is not recommended as it does not produce sufficient aeration.

Can I use any plant milk for the roux?

Yes — oat milk produces the most neutral, creamy result. Soy milk also works very well. Avoid coconut milk, which adds coconut flavor and can affect the texture of the roux.

How sweet is ermine frosting compared to regular buttercream?

Significantly less sweet — this is its defining characteristic. People accustomed to powdered sugar buttercream sometimes find ermine frosting surprisingly subtle at first; most consider it superior once they have tried it.

Tried this recipe? Leave a comment below and let us know how it turned out! Tag us on Instagram and Facebook — we love seeing your plant-powered creations. Looking for more elegant vegan baking and frosting recipes? Browse all recipes on Easy Vegan Recipes — new recipes posted every single week!