Tomato sauces for pasta are relatively straightforward to make. Whether you start with fresh tomatoes or canned, eventually they'll cook down enough to form a thick, noodle-coating sauce. Cheese sauces are typically quicker but require more skill. Knowing how and when to add the cheese is what makes or breaks your sauce.
The Basic Technique
Most cheese sauces are variations of simple white sauce. You can use milk and cream in varying proportions, and choose from a wide range of cheeses, but the technique is largely standardized.
Melt a tablespoon or two of butter in the bottom of a saucepan, over low heat, and add the same quantity of flour. Stir this roux for at least 5 minutes, making sure it doesn't brown. Turn down the heat if necessary.
Add milk or cream -- each tablespoon of flour thickens up to a cup of milk -- and whisk it into the hot roux until it's completely blended. Stir for another 5 to 10 minutes, until the milk is steamy and thickens to about the consistency of heavy cream.
Taste the resulting white sauce. If it still has the pasty flavor of uncooked flour, give it a few minutes longer.
Remove the sauce base from the burner, once you can no longer taste flour. Stir in the cheese -- up to 2 cups of finely shredded cheese for every cup of milk -- until it melts into the sauce base.
Some recipes call for the cheese to be added while the saucepan is on the burner, but it's safest to take it from the heat first. If the cheese overheats, its proteins "break" the sauce, leaving it grainy and lumpy instead of smooth and creamy.
Of course, this isn't the only way to make a cheese sauce.
- If you use heavy cream as your base, you can simply simmer the cream until it's reduced by 1/3 and then remove it from the heat and stir in the cheese. This makes a supremely rich sauce.
- Alternatively, instead of a roux, whisk the flour into 1/2 cup of cold milk. When the rest of the milk begins to steam, stir in the flour mixture.
Quick-thickening "instant" flour is a good choice for any cheese sauce. It thickens more quickly and doesn't have that raw flour taste. This cuts your prep time sharply. For an even faster sauce, heat your milk in the microwave ahead of time.
Choice of Cheese
The best cheeses for cheese sauce have a distinctive flavor and melt without becoming stringy. For example, mozzarella makes a fine topping for lasagna, but it's messy and inconvenient in a bowl of shells or orecchiette. Better options for sauce-making include Monterey Jack, Gruyere, Gouda and aged cheddar. Blue cheese makes an especially rich but pungent sauce. Feel free to experiment with different combinations of cheese to get exactly the flavor you want.
Finessing the Finish
Once you've mastered the basic technique, you have several ways to pump up the flavor in the sauce. Simmer onions, garlic or bay leaves in the milk as it heats, for example, then strain them out before thickening the sauce and adding the cheese.
If you find the sauce doesn't have a punchy enough cheese flavor -- a real issue for kids expecting the salty wallop of processed cheese products -- add a generous handful of grated Asiago, Romano or Parmigiano-Reggiano to the sauce. They provide concentrated cheese flavor, in the same way anchovies provide concentrated fish flavor. You can also add impact by stirring in a small quantity of buttermilk or plain yogurt just before serving. Their faintly acidic tang helps bring out the flavor of the cheeses.