German buttercream (Crème Mousseline)

With a rich and silky smooth custard-like character, this easy German Buttercream recipe (Crème Mousseline) is absolutely divine, my favorite buttercream frosting. It's composed of a simple pastry cream base that is enriched with butter, which is what makes it stand apart from more traditional sugar-heavy buttercreams. You can use Crème Mousseline on a variety of desserts from layer cakes and cupcakes to French macarons.

Jump to:

• 💡 What are the 5 types of buttercream?
• 5. German Buttercream
• 💡 What is German buttercream made of?
• 💡 Is Ermine frosting the same as German buttercream?
• 💡 Is German buttercream less sweet?
• 🌟 Why this is the best German buttercream frosting recipe
• 📝 Ingredient notes
• 👩‍🍳 How to make German buttercream
• ✨ What is German Buttercream used for
• 🎓 Expert tips
• ❓ German buttercream frosting FAQs
• 🍰 More frosting and filling recipes
• German buttercream (Crème Mousseline)

💡 What are the 5 types of buttercream?

Most people ask, what are the three types of buttercream? But there are actually more. So how many different types of buttercream frosting are there? Quite a few. When it comes to frosting and filling desserts you've got lots of choices! Here are the five most common.

1. American Buttercream (AMBC)

American Buttercream is the easiest to make and most commonly used type of frosting. It's very very sweet and is made by simply whipping butter and powdered sugar together, typically with a small amount of milk. American buttercream is fairly stable which makes it good for decorating. However, it is super sweet, less delicate, and less complex when it comes to the flavor profile.

2. Swiss Meringue Buttercream (SMBC)

Swiss Meringue Buttercream is a little less sweet and has more steps to make than American buttercream. As the name suggests Swiss Meringue buttercream has a Swiss meringue base, which makes it lighter and creamier. It's typically composed of egg whites and sugar cooked together over a double boiler and then whipped up with butter and a dash of salt and vanilla extract. It is super stable but you need to pay attention to the swiss meringue stage.

3. Italian Meringue Buttercream (IMBC)

Italian Meringue Buttercream uses the same ingredients and is somewhat similar to swiss meringue buttercream. But Italian Meringue Buttercream is sweetened with sugar syrup which makes it very stable but requires a little more technique especially when it comes to handling the sugar syrup and being accurate with its temperature.

4. French Buttercream

This one is light and smooth, a less-known buttercream, made with egg yolks (instead of egg white like the previous buttercream version), butter, and sugar syrup, similar to Italian meringue buttercream. French buttercream is a little more difficult to make and is naturally yellowish in color due to the egg yolk.

5. German Buttercream

Also called crème mousseline, it's basically the most delicious buttercream in my view, a different league from the rest. Cream mousseline is made of pastry cream and butter. German buttercream frosting has a lovely creamy texture, a superior custard-like taste profile, can be easily flavored, and most importantly not as sweet as the previous buttercream types.

It is used for French Classics such as Paris-Brest, Fraisier cake, but can be also flavored to make the most amazing Ferrero Rocher Cake or Lotus Biscoff Cake.

Making mousseline cream is also not hard at all but does require a few steps.

💡 What is German buttercream made of?

To begin, what is German buttercream? Also called Bavarian buttercream as well as mousseline cream, it's essentially a custard-based buttercream. You start with a pastry cream that is made with egg yolk, milk, and thickening ingredients such as cornstarch and flour. For more details please check my pastry cream recipe. Then, once the mixture comes to room temperature, it is whipped up with soft butter.

💡 Is Ermine frosting the same as German buttercream?

While these two frostings are similar, they are not the same. Ermine frosting is also called flour buttercream and has a pudding base. Basically, flour, milk, and sugar are cooked together to make ermine so no egg yolk is involved as in the German buttercream. German buttercream has a custard base that is similar to ermine but also egg yolk plays a key part.

💡 Is German buttercream less sweet?

Like most European-style frostings, custard buttercream is most definitely less sweet as well as both richer and more complex in flavor. It relies solely on its pastry cream base for all of its sweetness. So it's a fantastic option if you've ever wondered how do I make buttercream frosting for cakes less sweet!

🌟 Why this is the best German buttercream frosting recipe

1. It's easy - How to make German buttercream frosting? It's simple! Even if you're new to baking you should have no problem and great success just make sure to follow the recipe and pay attention to the ingredients, measurements, and temperatures.
2. The texture and taste is amazing - By using pastry cream as the base, which also makes it less sweet, this custard-like frosting has a lovely creamy and silky texture. So for example, when it comes to American buttercream vs German buttercream it's much more unique and complex.
3. Versatile frosting - This delicious buttercream can be used as a filling as well as to frost cakes, cupcakes, and more. It can also be flavored with a variety of other ingredients such as Nutella, Biscoff spread, and peanut butter or even cocoa powder to make chocolate German buttercream.

📝 Ingredient notes

1. Milk - Use whole milk for the creamiest texture.
2. Sugar - White granulated sugar is all you need. And be sure to check out my sugar guide to learn about different types of sugar in baking.
3. Egg - You only need the yolks of the eggs and they need to be at room temperature so that they blend properly with the other ingredients.
4. Cornstarch - Used to add thickness to the texture of the frosting. Alternatively, check my cornstarch substitute article.
5. Flour - Simple all-purpose flour is all you need. If you're interested in learning more about flour, please check out my flour guide.
6. Vanilla - I like to use vanilla bean paste. However, pure vanilla extract is another option or why not make your own vanilla extract?
7. Butter: Always use unsalted butter to control the level of salt. I also prefer using butter with an 82% fat content. For this recipe, the butter must be at room temperature. You can even make your own homemade butter.

🛒 You’ll find detailed measurements for all Ingredients in the printable version of the Recipe Card at the bottom of this post

👩‍🍳 How to make German buttercream

1. How to make pastry cream for the German buttercream

1. Whisk the sugar and egg yolks together in a large bowl using a hand whisk for about 1-2 minutes until slightly fluffy.
2. Whisk the cornstarch, flour, and vanilla bean paste into the egg yolk mixture until it's fully combined and it becomes a smooth paste.
3. Bring the milk to a simmer over medium heat in a saucepan. Then remove it from the stove.
4. Slowly pour the warm milk over the egg mixture while whisking vigorously.
5. Pour the mixture into the saucepan and then cook over medium heat for 1-2 minutes to thicken.
6. Strain the pastry cream to remove any lumps if necessary.
7. Incorporate the soft room temperature butter in 3 stages using a rubber spatula. Each addition should be fully incorporated before adding the next.
8. Transfer the pastry cream into a shallow bowl and cover the surface with plastic wrap so that skin won't form on top. Then allow it to cool to room temperature.

💡 Top Tip: As it thickens in the saucepan the cream may get lumpy at first, but just keep whisking and it will become smooth and glossy.

2. How to whip up the German buttercream

1. The pastry cream and butter must be at room temperature to make the crème mousseline.
2. Whip the softened butter for 1-2 minutes in a stand mixer fitted with a whisk attachment. Then add the pastry cream in 4 stages until the mixture reaches a fluffy but stable consistency. This will take about 1-2 minutes, be very careful not to over-whip.
3. If the buttercream seems soft once it's made, just put it in the fridge to chill for a bit before using.
4. Custard buttercream can be used fresh or stored in the refrigerator for 2-3 days.

💡 Top Tip: The cream will naturally set in the fridge due to its butter content (like any other buttercream) so if you want to pipe it, I recommend refrigerating the cream for no more than 1-2 hours.

✨ What is German Buttercream used for

This frosting can be used in combination with numerous other dessert recipes and flavored too. The possibilities are endless!

To get started, how to flavor German buttercream? It's actually pretty easy and done by simply whipping in your choice of flavorings into the butter and then adding the pastry cream to complete the crème mousseline recipe. Some of my favorite ways to flavor the buttercream are with ground cinnamon, cocoa powder, Biscoff butter, Nutella, peanut butter, and hazelnut praline.

And of course, you can use the frosting on cakes, cupcakes, cookies, or as filling for classic french pastry like choux! Just check out all these delicious recipes to use your wonderful and easy custard buttercream!

🎓 Expert tips

1. Use high-quality ingredients for the best flavor. European butter with an 82% fat content, whole milk, good eggs, and top-quality vanilla makes all the difference in taste and texture.
2. Allow the egg yolks to come to room temperature so that the pastry cream comes together properly.
3. When adding the milk to the egg mixture of the pastry cream you must do it slowly while stirring constantly with a whisk.
4. If necessary, strain any lumps out of the pastry cream after it has been thickened.
5. The pastry cream and butter must be at room temperature before you can begin making the frosting.
6. Do not over whip the frosting. Stop once it becomes fluffy, which takes about 1-2 minutes, or it can break and become runny.

❓ German buttercream frosting FAQs

🍰 More frosting and filling recipes