Bechamel or white sauce is one of the group of French sauces referred to as mother sauces. The base for others. Mastering these basics let's you create a variety of other increasingly more complex sauces and dishes.
2 tablespoons of flour
2 tablespoons butter
1 cup milk, scalded
Salt and pepper to taste
Pinch of nutmeg-optional
In a medium saucepan, over medium heat, melt the butter.
Remove from heat, whisk in flour.
Beat until smooth, this is called a roux and is the thickener for the sauce. The end thickness depends on how much roux you use, for thicker increase for thinner decrease. The only important thing to keep in mind is to keep the butter to flour ratio 1 to 1.
Gradually add in scalded milk, whisking continuously.
Add salt, pepper or spices if using.
Return to heat and simmer until desired thickness anywhere from 10 to 20 minutes. Stir often to prevent scorching.
Yield is about 1 cup of sauce.
Sounds easy enough right? I can't tell you the number of people who have trouble with this. Everything from it being all lumpy to it separating or curdling.
Some tips to prevent lumps.
Don't over heat the butter or the milk. Melt the butter, don't heat it to bubbling. Heat toughens the gluten in the flour and you want to hold that off until it is incorporated into the milk. Same with the milk. Scald it, don't bring it to a boil. When bubbles start to form around the edge, it should be hot enough.
Add the milk hot. If you add cold milk the roux hardens into lumps. By the time the milk is warmed, the roux has cooked into little balls rather than being incorporated into the sauce.
Add the milk gradually. If you dump all the milk in at once, it starts to cook the roux right away. By the time you start whisking, it can already start to clump.
Add the milk off direct heat. It prevents scorching the roux and it also gives you a few extra seconds while working to incorporate it into the sauce.
Sounds like a lot to remember but it isn't really and it isn't time consuming either. The entire mixing in the milk should only take a couple of minutes. Why bother practicing this technique? You use it when making hollandaise, mayonnaise, custards or aioli. Practice makes perfect.
If worst comes to worst and your attempt is lumpy you can strain it or a couple of pulses of an immersion blender should smooth it out.
To prevent separating or curdling, add the milk all at the same time. Don't decide half way through cooking to add more. Cooking toughens the protein(at least I think it's the protein) in milk. Adding more after cooking has started, you have two different thickness of milk which won't blend. One that has incorporated into the sauce and the other that won't. This applies to anything you are cooking in milk, scalloped potatoes, rice pudding, cream sauces.
If your sauce is too thick, thin it with a little stock, add it in a tablespoon at a time. A little goes a long way.
Are there shortcuts? I'd be lying if I said I was this careful all the time. I've used cold milk and whisked like crazy. I've done it over heat and whisked like crazy. I've dumped all the milk in at once and whisked like crazy. It is actually more effort to do it wrong. It seems like you're saving time and effort but you have to be faster, whisk far more and longer and be prepared for it to not turn out just so. That doesn't mean I haven't.
Why all this fuss over a little sauce?
On it's own you can serve it with fish or poultry. It is also used in lasagna and mousaka.
Add grated Parmesan cheese and you have a quick and dirty Alfredo sauce. Throw some bacon into that and you have Pasta Carbonara.
Add a couple of tablespoons of tomato paste, quick and dirty Rose sauce. Goes with just about any type of pasta.
Add grated Parmesan and shredded Gruyere cheese, 1/2 cup each, and you have the classic Mornay or cheese sauce. You can substitute any cheese you like, even my guilty pleasure Cheez Whiz. Cheese sauces are delicious with all kinds of vegetables, chicken or egg dishes.
Add a tablespoon or two of prepared mustard or a teaspoon of mustard powder and you have a perfect sauce for pork or chicken.
Add a cup of onions, sweated or caramelized then pureed and you have the classic Soubise. Delicious with pasta, fish, chicken or pork.
You can add any variety of herbs, fresh or dried. Rosemary with lamb or pork, oregano or dill for chicken, dill for fish, basil for pasta etc etc etc.
One basic sauce, one fairly simple technique and an endless variety of taste. Perfect to perk up an ordinary meal. The fancy French names you can throw around are just a bonus. Enjoy.