Sauce mousseline

Sauce mousseline is a hollandaise that is refined with whipping cream. It goes very well with fish and asparagus. I used to prepare hollandaise in the past according to the recipe posted some years ago, but this asparagus season I started with Roux's recipe. What a great decision! It beats every hollandaise I had before. It is not beaten over steam, but on a heat diffuser, however I am not sure if that is what makes the difference. On Saturday I found some fava beans in a tiny shop, and I was thrilled, because the whole last year I didn't see them anywhere. I decided to prepare some for lunch today, among asparagus and fish. The gorgeous organic sea bass in the freezer seemed to be just perfect for this light(?) spring dish, that I served with a spalsh of lemon oil.


Ingredients:
1 tbsp white wine vinegar
1 tsp white peppercorns, crushed
4 egg yolks
250 g freshly clarified butter, lukewarm
75 ml whipping cream
juice of 1/2 lemon
salt


In a saucepan over a low heat, mix the wine vinegar, 4 tbsp cold water and the crushed pepper. Allow to bubble until the liquid has reduced by one-third. Leave to cool completely.
Add the egg yolks to the cold reduction and whisk to combine. Set the pan (on a heat diffuser if you have one) over a very low heat and continue whisking. Gradually increase the heat so that the sauce gradually emulsifies, becoming very smooth and creamy after 8-10 minutes. Don’t let the temperature rise above 65°C.
Take the pan off the heat and, while still whisking, pour in the clarified butter in a steady stream. Season with salt, to taste. Whisk the cream in a mixing bowl until soft peaks form when the whisk is removed from the bowl. Fold the cream into the sauce and then at the last moment, stir in the lemon juice. (source:UKTV)