Or – «Bechamel ou Velouté aux Oignons».
This is a classic sauce for the lasagna, or whenever you might want a rich, creamy sauce. It’s not much more difficult than using a mix from a packet, but a lot better tasting – AND – you get the added bonus of tailoring the sauce to your own particular whims. I doubled the amount of this sauce and it seemed to work out perfectly for my lasagna. For the lasagna, I would have everything else good to go and then do this sauce – the instructions for making it ahead and keeping it ‘fresh’ seem like a lot of bother to me.
•1/2 the cooked onions from the tomato sauce
•6 tbsp butter
•1/2 cup flour, scooped and leveled
•3 to 3-1/2 cups hot liquid (milk plus chicken stock and/or mushroom juices – about 16 oz. of sliced satueed ‘shrooms are listed as an optional filling – so if you have any juices from that pan, go ahead and use them, I didn’t. For the liquid, I didn’t want to just use skim milk and chicken stock, so used the last of the heavy cream I had bought to make the wine pie earlier. The taste was lovely, but I may go for whole or 2% milk next time.
•1/3 cup dry white wine or dry white french vermouth
•Salt and pepper to taste
Blend the onions with the butter in a heavy-bottomed 2-quart saucepan over moderate heat. When butter is bubbling, blend in the flour and cook, stirring with a wooden spoon, for 2 minutes without browning the flour at all (my roux got a wee, tiny bit golden, but was still good). Remove from heat. When mixture has stopped bubbling, pour in two-thirds of the hot liquid all at once, blending vigorously with a wire whip. Blend in more, leaving about 1⁄2 cup for later. Beat in the wine, and set over moderately high heat, stirring, until sauce comes to a boil. Thin out, if necessary, with the remaining liquid; sauce should be thick enough to coat a spoon fairly heavily. Boil, stirring frequently with a wooden spoon, for 4 to 5 minutes; beat in salt and pepper to taste.
If not used immediately, keep over a pan of simmering water, stirring occasionally. If done in advance, clean sauce off sides of pan with a rubber spatula, and float a film of milk over surface to keep a skin from forming; beat over heat to liquify before using, and thin out with droplets of milk if sauce seems too thick.