What do stocks and sauces have to do with comfort food? Well, look at biscuits and gravy, there is no doubt that biscuits and gravy are comfort food. That gravy is Bechamel, it may not be classic Bechamel, but it's Bechamel nonetheless.
Then there's chicken soup. You really can't make chicken soup without chicken stock. How about French onion soup, that is an all time classic comfort food dish. It's made with beef stock.
Whether it's comfort food or nouveau cuisine, stocks and sauces play a critical role.
Stocks are the basis for so much of cooking and the starting point for many of the sauces we use. I want you to learn to do them right, I can’t tell you how many “professional cooks, sous chefs, and chefs” make them wrong every time. In many restaurants, when they roast the bones they slather them in tomato paste. By the time the bones have finished roasting the tomato paste is burned. Then, they treat the stock pot like a waste bin. They throw trimmings, peelings and all manner of refuge into it. Then when they do make the the stock they put it on the stove, turn the heat up to incinerate, and let it rip! It's absurd.
Why, you ask? Because when you are making stock one of the goals you are trying to achieve is a nice clear stock without too many impurities. If you burn the bones when you roast them all that carbon is going to cook into your stock. When the stock boils rapidly, wildly, and continuously the impurities break down and you never get them out. Then your stock is cloudy and tastes bitter. That is why.
Stock is not an afterthought or something to cheat on. It is a very important part of a chef's repertoire, and it should be a part of yours. If you start with excellent stock the rest of the work is easy.
There are several kinds of stock, vegetable stock, fish stock, light and dark chicken stock, veal stock, and you can do specialized stocks. In the end there are a variety of stocks out there, some associated with a particular cuisine, like dashi a fish and kelp stock, and some are universal, like veal stock. Stocks are always made from bones, with the exception of vegetable stock. Each type of stock has an approximate cooking time. The length of time it takes to extract the flavor from the bones.
Your mirepoix needs to be cut correctly. It makes no sense to drop a whole carrot into a stock pot, don't laugh, I've seen it. For example, fish stock takes about 40 minutes to cook so you don’t want your mirepoix to be 3” x 3” x 3” because the flavor of the vegetables will never release.
Stocks have a correct ratio to get the proper flavor. It is 5 parts bones to 1 part vegetable, and 2 parts onion to 1 part each of carrot and celery. For example, If you have 5 pounds of chicken bones, you should have 1 pound of aromatic vegetables. So you would need 8 ounces of onion and 4 ounces each of celery and carrot.
When you make vegetable stock that ratio holds true. To get the proper flavor you need 2 parts onion to one part celery and carrot.
A last note: stock is the one thing you do not salt. For many of the applications you are going to use it for, you are going to reduce the stock and when you reduce the stock the salt is going to concentrate and your food is going to be too salty.
Mother sauces, or leading sauces, form the foundation for the entire classical French repertoire of hot sauces. They are: bechamel, espagnole or brown sauce, hollandaise or mayonnaise, tomato and veloute. They are distinguished by the liquids and thickeners used to make them and they can be changed to create a wide variety of small or compound sauces.
So, mother sauces or leading sauces are sauces that hold up well, stand on their own, form a basis for other sauces, and stand the test of time.
Any of a variety of French sauces made by adding ingredients to a leading or mother sauce. They are grouped together according to their mother sauce.
Broths differ from stock in that they are traditionally made using meat rather than bones. Other than that difference they are made the same way, though cooking times needn't go so long. Your vegetable cuts need to be smaller since your cooking times are shorter, relative to the type of broth you're making.