Matthew's Journal

I was wasting time on the internet, and came across a blog post about Soubise, a savoury onion sauce. AIUI, it originally involved rice (Escoffier describes it thus), but more conventionally is Béchamel sauce with sweated onions added. Serious Eats suggested there was a modern, lighter, variation, which was to use cream instead of Béchamel[0]. That seemed worth a try, so I made one this evening, and it was pretty good.

Here's what I did (which was too much sauce for 2 people, would certainly have done 3, and probably 4)[1]:
25 butter
2 medium onions, thinly sliced
300ml double cream

Melt the butter over a medium heat until foaming; add the onions and cook gently (stirring frequently) for ~20 minutes, until properly soft and any liquid has gone. The aim is to avoid caramelising the onions, so resist the temptation to fry them hot!
Pour in the cream and simmer for about 5 minutes until it starts to thicken.
Blend to as nearly-smooth as you can be bothered with, season with a little salt and some black pepper, and serve.

You could choose to flavour this sauce further (Serious Eats suggest 1tsp curry powder; I'd think about chilli flakes), but it's good as-is.

[0] definite win, since I haven't successfully made white sauce in a very long time
[1] the recipe is taken from Serious Eats (an American site) which uses 2 tbsp butter (about 28g) and 1.5 cups of heavy cream (360ml, but heavy cream's a bit less fatty than double cream).