Soubise sauce is a compound French sauce that is made by combining the simple sauce béchamel with pureed onions and heavy cream. The resulting onion sauce is typically served with meat or eggs.
Melt 2 tablespoons (30 ml) of butter in a medium saucepan.
Add 2 tablespoons (30 gm) of flour to the butter to form a roux.
This is the first stage of any French sauce.
Always keep the ratio of butter to flour equal when making a roux.
If you’re making the sauce thicker, use 3 tablespoons (45 ml) of each. If making the sauce thinner, use 1 tablespoon (15 ml) of each.
Cook the roux over high heat, stirring constantly until it turns a pale straw color.
Remove the roux from the heat and let it cool slightly while you warm 1 cup (237 ml) of milk in a separate pan until it’s simmering.
Slowly incorporate the milk into the roux a few tablespoons at a time.
Adding the warmed milk slowly helps to thicken the sauce faster.
Heat the sauce until it is nearly boiling to thicken it.
It should coat the back of a spoon that has been dipped into it when it is finished.
Remove the sauce from the heat and let it cool for a few minutes.
Heat 2 tablespoons (30 ml) of butter in a sauté pan and add the onions to the melted butter.
sauté the onions until they are soft and translucent.
Transfer the onions to a food processor or blender and pulse them until they become smooth and pureed.
Stir the cooked and pureed onions into the béchamel sauce.
Add 3 tablespoons (45 ml) of heavy cream, 1 tablespoon (15 ml) at a time, to the sauce.
Stir well after adding each spoon.