Crème Mousseline

• 1,135 grams (2½ pounds) freshly made, still-warm Crème Pâtissière
• 340 grams

Prepare your mise en place.

If the pastry cream is very warm, place it in the bowl of a standing electric mixer fitted with the paddle attachment and beat on medium for a few minutes to cool it slightly.

With the motor running, add the butter, a bit at a time, beating until it is completely incorporated and the mixture is very light and fluffy, scraping down the sides of