- 250g (87/8 oz) onion.
- 60g (41/2 tablespoons) butter.
- 12g plain flour.
- 21/2dl (1 cup) clear veal or chicken bouillon, or 21/2dl milk.
- 2 tablespoons creme fraiche.
- pinch nutmeg.
- pinch caster sugar.
- salt and pepper.
Peel and wash the onions. Slice them as finely as possible. If the onions are old, blanch them. Otherwise, put them in a thick bottom saucepan with 40g of butter and stew them gently (sweat off), covered, for 20-25 minutes (without coloring them).
When this is done, stir in the flour, allow to cook for 5 minutes. Stir in the bouillon or milk and add the seasoning. Bring gently to the boil while stiring constantly. Cover and let the sauce cook, at a very gentle simmer for at least 45 minutes. Stir from time to time.
Force the sauce through a chinois and put back on the heat. Then add the rest of the butter and the creme fraiche. Let the sauce cook for another 5 minutes. Check the seasoning.
Set aside in a bain-marie until serving time.
"Make [food] simple and let things taste of what they are."
Curnonsky (Maurice Edmond Sailland 1872-1956)