HOW TO MAKE STOCKS
Fonds de cuisine should be on any chef's or home cook's basic arsenal. Because, that's what it is - the fundamentals of cooking. What are we talking about? Stocks! The liquids that are full of flavour and can be mixed in with other dishes that require some aromatic touch that they cannot develop on their own. Well, at least that's what stocks are used for. Most common use of stocks are sauces and many soups, and they can also be the basis in simmering liquids when you cook meat or fish, and if you make a risotto. Now, most people I know don't make their own stocks; they buy some cubes (essentially a stock concentrate) but the flavour is so much better if you have your own home-made stock to work with. And, since it is liquid, you can make a big batch of it and freeze it, without damaging its texture and without losing much flavour.
Stocks are based on either meat, poultry, fish, or vegetables. Well, vegetables are added to all stocks due to their nice flavour, but you can make a purely vegetable-rich stock without any meat. The good thing about a stock is that you don't need to use fine cuts of meat. Use anything that is left over from it, for example bones, or chicken legs. It is good to have some pure meat in the stock as well, since it adds even more flavour, but as said, it doesn't have to be a top quality cut.
There are three types of stocks: white, brown, and fumets. They all differ in the basic method of preparation. White stocks are made by simmering all ingredients over gentle heat. Brown stocks need to have browned (roasted) ingredients prior to simmering. In fumets (french for "scents"), the ingredients are sweated or smothered prior to simmering. Fumets can also make use of dry white wine, bringing even more flavour to the stock.
When choosing bones, the best ones are the meaty bones, but also neck or back bones are good. Also, the younger animals have a higher content of loose connective tissue that extracts nicely into the liquid, giving the stock a good body. Before using, the bones must be rinsed and the blood should be removed. If you want to make a brown stock, roast the bones in a thinly oiled pan for over half an hour in 220C/425F, turning them from time to time, until their color becomes brown.
Besides bones, you need vegetables. A traditional mixture consists of 2 parts onion, 1 part carrot, 1 part celery. The total amount in meat or fish stocks should be about 0.5 kg per 6 liter/1.6 gal of water. For vegetable stocks, the amount is of course much higher, and also additional vegetables are used to complement the flavours. The amount of meat bones for the above water volume should be around 3.5 kg. For fish or shellfish stocks, more bones are used, about the same amount as the amount of water. Besides these basic ingredients, you will also need some very aromatic thingies to add at the end of cooking. These can be bouquet garni or sachet d'epices - essentially a package of ingredients that release their flavours quickly but are too volatile to use during the entire cooking. These ingredients include some combination of a few parsley stems, a sprig of thyme, a crashed garlic clove, a few crashed peppercorns, and a bay leaf. Read more on bouquet garni and sachet d'epices here.
When making a stock, it is important to simmer, not to boil the liquid. You want to minimize the evaporation of the aromatic molecules that you just gently extracted from your food! Also, a pot that is high and not so wide will reduce the evaporation surface. When the stock is simmering, you also want to skim the greasy untasty fats that accumulate on the surface. Actually, one good trick to use here (if you make a chicken stock) is to put the chicken carcass into a boiling water for about 2 minutes, and then remove it. During this short time, lots of coagulated blood and small fats will float to the surface, and the chicken will be fairly clean. You can also quickly rinse it afterwards in cold water. Then use this chicken for your stock, as usual.
At the end, also make sure to strain the stock, then cool it (preferably quickly, on an ice bath to prevent the bacterial growth). Remove the fat that has accumulated on the surface. Now, look at your stock. Is the color and the clarity appealing? How does it taste? You should sense all the main ingredients in your stock, and the color will be determined on whether you have browned the ingredients or not (white vs. brown). Vegetables like carrots will also contribute to the color (golden). Good luck with your stock! Try to create your own, maybe by first modifying someone's stock recipe.