How to Make Crème Mousseline (Whipped Butter + Pastry Cream)
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Ever wondered how to make those fancy dessert fillings at home? Our Crème Mousseline recipe is your easy step-by-step guide to creating a rich, buttery cream perfect for any treat.
Crème Mousseline 101
Creme mousseline is essentially pastry cream mixed with softened whipped butter.
The cream is much richer and noticeably thicker than regular pastry cream, thanks to lots of butter added. That makes it easy to pipe and keep its shape well, even under heavy decorations.
Creme mousseline is perfect for layered cakes, topping cupcakes and muffins, or filling cream puffs or eclairs if you’re looking for a sturdy filling that retains its shape.
(If you’d rather use a lighter filling that’s not so sturdy, stick to regular pastry cream, or even lighten it up by mixing with whipped cream and gelatin, making creme diplomat.)
In this recipe, I show how to turn creme patisserie into creme mousseline, but nothing stops you from using any other pastry cream.
Here are some that I’ve already covered:
Scaling
The main thing about this recipe is that you scale the amount of butter to the amount of milk (or other base liquid) you use in the pastry cream.
Everyone has their favorite ratio, and for me, it’s one stick of butter (8 tbsp or 4oz or ~113g) to 1 cup of milk (240ml). You can add more butter to make it richer, but the above ratio makes the cream nice and sturdy without making it overly rich.
Once you whip it a couple of times, feel free to start adjusting the amount of butter to your liking.
Ingredients and Substitutes
- Milk: Whole fat works best, but skim should be okay too. Milk alternatives also work well, but the final flavor will differ slightly. When using a vegan milk alternative, check whether it’s the regular or sweet variety. If the latter, reduce the amount of sugar by half and add more after cooking the cream if needed.
- Cornstarch: Cornstarch is ideal as it has a relatively high thickening temperature. You can also use potato starch (half the amount), but let the cooked milk mixture cool down a bit before adding it to the eggs so the egg mixture doesn’t thicken too quickly. Check out my article on cornstarch versus potato starch for more details.
- Sugar: Regular white sugar works well, but feel free to use any sweetener you like. Remember to adjust the amount when using alternatives like xylitol or stevia.
- Vanilla Extract: Vanilla extract is what gives this pastry cream its flavor. I typically use the extract because it simplifies the workflow compared to vanilla beans (which many other recipes recommend). I cover using vanilla beans later in the article.
- Unsalted Butter: Plain unsalted butter is all you need.
How to Make Creme Mousseline
Here’s a brief overview of the recipe below:
- Make pastry cream and let it cool to room temperature.
- Cut butter into small chunks and let it warm up to room temperature.
- When both are at room temperature, whip the butter using a hand mixer, then add the pastry cream bit by bit while mixing continuously.
- Refrigerate until ready to use.
Now, let’s jump into the details.
Step 1: Make Pastry Cream
- Boil Milk: Measure the milk into a pot and stir in the vanilla extract and half the sugar. Bring the mixture close to a boil.
- Prep Yolks: While the milk is heating, whisk the yolks in a large bowl, then stir in the cornstarch and the remaining sugar. Set aside.
- Temper Eggs: When the milk is close to boiling, remove it from the heat. Gradually pour a couple of tablespoons of the hot milk into the yolk mixture, constantly whisking to prevent the yolks from curdling. Repeat this process 3 to 4 times until you’ve incorporated all the milk. Keep stirring throughout.
- Cook Until Thick and Bubbly: Return the combined mixture to the pot you used for the milk. Cook it over low or medium heat, stirring constantly, until it thickens and starts to bubble. Depending on the pot and heat intensity, this typically takes 2 to 4 minutes. Avoid rushing the process to prevent the yolks from curdling.
Pour the mixture into the pot- Cook and stir until it thickens
- Take Off the Heat and Whisk: Once the mixture is thick, remove the pot from the heat and continue whisking for about a minute, bringing the mixture past the point of maximum thickness.
- Stir in Butter: Add the butter to the pot and stir until it melts and integrates into the cream.
- Add butter to the pot
- Stir until butter is incorporated
- Taste Test: Sample the cream (be cautious; it’s hot) and add more sugar or vanilla extract if necessary.
- Cover and Chill: Place plastic wrap directly on the surface of the pastry cream to prevent a crust from forming. Leave it at room temperature until it cools to about room temperature. Feel free to use the fridge or a cold bath to speed things up.
- Cover with plastic wrap
- Cool to room temperature
Step 2: Prep Butter
- Soften butter. Remove the butter from the refrigerator, slice it into chunks, and let it soften at room temperature. Do not warm it in the microwave or melt it on the stove; it has to be soft, not melted.
- Wait. Wait until both butter and pastry cream are at about room temperature.
Step 3: Combine
- Whip butter. In a mixing bowl, add the softened butter and whip it with a mixer for at least 20 to 30 seconds at medium speed until well-aerated.
- Add pastry cream. Gradually add the pastry cream to the whipped butter, one spoonful at a time, mixing continuously until all the pastry cream is incorporated and the mixture is smooth.
- Gradually add the pastry cream
- And mix until smooth
- Taste test. Taste the cream and adjust the flavor as needed. Add powdered sugar for sweetness or vanilla extract if the flavor isn’t strong enough.
- Refrigerate. Creme mousseline is relatively soft immediately after whipping. You can use it immediately if you’re using it for a filling that doesn’t need to hold shape. Otherwise, refrigerate it for an hour to firm up for piping.
Tips
- Chill on a plate. To speed up chilling, pour the pastry cream into a large plate or bowl. A larger surface area will help it lose warmth faster.
- Mind temperatures. Both the pastry cream and the butter should be at room temperature. If the pudding is too hot, it’ll melt the butter, and we definitely don’t want that.
- Scrape the bowl. Use a silicone spatula to scrape down the sides of the bowl and incorporate all ingredients for an even mix.
- Make it in advance. Creme mousseline keeps shape easily for 3 to 4 days, so you can easily prepare it the day before you need it.
- Warm up before piping. The cream becomes very stiff after sitting in the fridge for a couple of hours and might be slightly difficult to pipe, especially if you’re using small tips. Because of that, it’s best to allow it to warm up at room temperature for an hour before piping.
Storage
Once prepared, you can store creme mousseline for 3 to 4 days in the fridge. Make sure the container is sealed tightly so that it doesn’t absorb any smells.
Servings: 3.5 cups
Equipment
Ingredients
- 2 cups milk ~480g
- 4 egg yolks medium or large (about 60-70g)
- 4 tablespoons cornstarch ~40g
- 7 tablespoons sugar ~87g
- 2 teaspoons vanilla extract
- 2 tbsp unsalted butter ~28g, for pastry cream
- 8 oz unsalted butter ~226g, for whipping
Instructions
Make Pastry Cream
- Boil Milk: In a pot, mix milk with vanilla extract and half the sugar, and heat until almost boiling.2 cups milk, 2 teaspoons vanilla extract, 7 tablespoons sugar
- Prep Yolks: Whisk yolks in a bowl, then mix in cornstarch and the remaining sugar.4 egg yolks, 4 tablespoons cornstarch
- Temper Eggs: Gradually add a few tablespoons of hot milk to the yolk mixture, whisking constantly to avoid curdling. Repeat until all milk is incorporated.
- Thicken Cream: Return mixture to the pot and cook on low/medium heat, stirring constantly, until it thickens and bubbles (2-4 minutes).
- Off Heat Whisking: Once thick, remove from heat and whisk for another minute.
- Add Butter: Stir the cold butter into the mixture until melted and integrated.2 tbsp unsalted butter
- Taste and Adjust: Taste the cream and add more sugar or vanilla if needed.
- Chill: Cover with plastic wrap touching the cream's surface to avoid crust formation. Cool until it's at room temperature, either on the counter or use the fridge or a cold water bath to speed things up.
Prep Butter
- Soften Butter: Remove butter from the fridge, cut into chunks, and let it reach room temperature to ensure it's soft but not melted.8 oz unsalted butter
Combine
- Whip Butter: Whip the softened butter in a mixing bowl on medium speed for 20-30 seconds until airy.
- Mix with Pastry Cream: Gradually add the pastry cream to the whipped butter, mixing continuously until fully incorporated and smooth.
- Adjust Flavor: Taste and adjust by adding more powdered sugar or vanilla if needed.
- Refrigerate: If the mousseline cream needs to hold shape for piping, refrigerate it for an hour to firm up; otherwise, you can use it immediately.
Tried this recipe?Let us know how it was!