Great goal! The perfect buttercream is one that doesn’t slide, is stable, spreads well, and most importantly, doesn’t fall off your cake even when it’s hot. The secret lies in creating the right emulsion and in the strict ratio of butter and sugar.

The most stable buttercreams used to cover cakes are Swiss and Italian meringue buttercreams (SMBC and IMBC), as the heat-treated protein base provides the stability.

However, if you’re looking for a cream that’s faster but still very stable and reminiscent of the classic Hungarian cream, try Boiled Buttercream (which is achieved with a milk-soda base).

🎂 The Perfect and Stable Boiled Buttercream Recipe
This cream stabilizes the protein and fat with starch and heat, so it is guaranteed to be fixed and will not fall.

📋 Ingredients
I. Cream Base (The Boiled Part)
Ingredients Quantity Notes
Milk 3 dl Full-fat milk is best.
Granulated sugar 100 g
Flour (plain) 2 heaped tablespoons (approx. 30 g)
Vanilla extract or stick 1 teaspoon / 1/2 stick
II. Butter Part (The Stabilizer)
Ingredients Quantity Notes
Butter (unsalted) 250 g KEY: Room temperature!

Powdered sugar 100 g
🛠️ Preparation
I. The Boiled Cream Base (Baking Soda)
Mixing: In a saucepan, mix the flour and sugar until smooth.
Add: Gradually add milk, stirring until smooth, so there are no lumps. Add vanilla.
Thicken: Cook over medium heat, stirring constantly, until thick. When thickened and starting to “puff”, cook for 1 more minute.

Cooling (KEY!): Pour the heavy cream into a clean, flat bowl. Cover the surface tightly with plastic wrap (to prevent a skin from forming!). Let cool completely to room temperature (this can take several hours). The butter and the cooked cream must be at the same temperature for a stable emulsion.
II. Making the Buttercream

Cream the butter: In a large bowl (preferably in a stand mixer or with a hand mixer), cream together the room temperature butter and powdered sugar. Beat for at least 5 minutes until white and light.
Assembly: Add the completely cooled (but not refrigerated!) cooked cream to this butter base, one tablespoon at a time. After each spoonful, stir until smooth before adding the next.
Mixing: Stir until all the cooked base is incorporated and you have a smooth, shiny, extremely stable buttercream.
💡 Tips for Stability
Temperature: This is the most important thing! If the cooked base is warmer than the butter, the cream will liquefy. If it is colder, the butter will precipitate and become greasy and lumpy.
Refrigeration: If the finished cream is too soft, refrigerate it for $10 \text{ minutes}$, then whip it again. It can also be stored in the refrigerator when hard, but let it soften a little before using and stir it.
Flavoring: You can then flavor the finished cream with cocoa powder, rum, coffee, or melted (but cooled!) chocolate.
This buttercream is perfect for covering cakes because it holds its shape well and is stable.