I had been debating between choosing mousseline butter cream or swiss meringue when I decided to make this cake, made with fresh eggs, and sweet butter. Topped with whole walnuts, encased between layers of cake sponge and finished with a creamy decadent mousseline buttercream, it smelled awesome and the batter was delicious. I could have ate it all myself! All I know is that this versatile delicious cream is basically pastry cream mixed with butter. My thinking is a little of this incredible cream on a cake goes a long way…. light, fluffy and definitely rich….
Source: Cake Recipe