Soubise (pronounced "soo-beez") is a rich French onion sauce. It is made by combining the Mother Sauce known as béchamel with cooked onions that have been puréed, and it is typically served with proteins, such as eggs, grilled meat, poultry, or fish.
The French term can also be applied to dishes that come with a soubise sauce, such as "eggs à la soubise."
Mornay sauce is a classic French white sauce. The compound made from adding grated hard or semi-hard cheese — typically, Parmesan, Swiss, or a 50-50 ratio of each — to the Mother Sauce known as béchamel.
The cheese sauce is often served with eggs, vegetables, chicken, and seafood and is a key component in the Kentucky Hot Brown.
Calling all home cooks: if you haven't been acquainted yet with béchamel sauce, it's time you learned a thing or two about it. Chances are you've eaten this white sauce more than a few times in your life, whether layered in moussaka, drizzled on a croque monsieur, or as a component in other classic courses. 
Béchamel is over 300 years old, and is such a key element of traditional French cuisine that it actually serves as the base for many other sauces (see variations after the jump). The white sauce begins with a roux, and then scalded milk is gradually added, until the consistency is smooth and thick. Once you've mastered the recipe, you can use it to make a filling for white lasagna or to mix together a cheese sauce for nontraditional nachos. What are you waiting for? Get the recipe when you read more.
What do you get when you combine crispy, salty chips with spicy, melty cheese and fresh, flaky crab? Some amazingly delicious nachos! Between the newly-picked crab, the homemade pico de gallo, and the pepper-jack béchamel, these nachos are more gourmet than ghetto — who said Mexican food can't be high end?
The recipe calls for blue corn tortilla chips, but any tortilla chip would work. I used frozen corn — make sure it's thawed, you don't want soggy nachos — because fresh isn't in season. These nachos were incredibly tasty and I'm definitely making them again. To look at the recipe, read more
Roux (pronunciation is roo)
A mixture of fat (butter, oil) and flour gently cooked together. The time allowed for the cooking determines the color of the roux. There are three types of roux—brown, blond and white—although all are made in essentially the same way by melting butter and stirring in flour. Roux is used to thicken soups and sauces and is a staple of Cajun and Creole dishes.
Béchamel A basic white sauce that is used as the base for other sauces. This basic sauce, one of the mother sauces of French cuisine, is usually made by whisking scalded milk gradually into a white flour-butter mixture. The thickness of the final sauce depends on the proportions of butter and flour to the milk.
