You can use it for your cream puffs, donuts, cakes, cupcakes, etc. The main ingredient of this cream is butter, but for mousseline cream you need also milk, sugar, flour and vanilla extract. The cream has lightly vanilla smell. I often use it for cupcakes on the top, but add a food coloring. It looks very nice and has good consistency. You can store ready mousseline cream in the refrigerator for 2 days. It keeps its look and taste.
I’ve found this recipe here.