A stock is a flavorful liquid prepared by simmering bones, shells, or vegetables in water until the water takes on the flavors, smells, and color of the simmered ingredients. In France they are sometimes called Fonds du Cuisine, the "foundation of cooking." There are three basic types of stocks, white, brown, and fumets.

White stocks are made by adding all the ingredients of the stock into cold water and slowly bringing them to a simmer. This kind of stock goes best when adding to cream sauces or when a light colored subtly flavored stock is needed. To avoid the stock from getting cloudy you should blanche the bones first.

Brown stocks are made by browning the bones and mirepoix, commonly in the oven or stove top, before adding them to the water.(for small batches it is easier to heat bones on stove, larger batches are quicker in the oven) Brown stocks will have a stronger flavor then white stocks. One source claims that if a brown stock is made starting with cold water and not allowed to boil the broth will still remain clear.

Fumets are made by sweating the main ingredients of the stock before simmering, (most of the time the ingredients are simmered in white wine.

What kinds of bones should you use? Bones of young animals have more cartilage and connective tissues, which will break down into gelatin and give the stock body. Knuckle, back and neck bones are great for stock too. Thaw bones before simmering them into stock, cutting bones into 3 inch pieces will help speed the process up. Bones should be rinsed to wash away blood and impurities that can ruin the stock.

DO NOT LET THE STOCK BOIL it will dispense the fat and make a greasy tasting stock. You can cool the stock and when the fat solidifies on the top remove it the next day. Always start with cold water when making a stock, to prevent the starches on the vegetables surface from expanding.

Add a sachet or bouquet garni to the stock to add more flavor. Some people choose not to tie the boquet or sachet since they are going to strain the stock when its finished, but tying the bouquet makes it easier to remove if the herbs begin to impart to much flavor.

Another way to make the stock darker and richer in flavor is to add tomato paste to the browned ingredients. Red wine can be used to deglaze the pan that the browned ingredients are cooked in. Trimming and dried mushrooms can also be added to add more flavor to the stock.

Stock pots are the tallest pots in the kitchen, this is so they have less surface area on the flame to reduce the amount of evaporation. Keep a ladle or skimmer ready to remove impurities throughout the cooking process. For larger batches a kitchen may decide to invest in a tilting kettle, but expect to pay $10-20 thousand for one. Cheesecloth, sieve, or colander will be needed to strain the stock when it is finished. An ice paddle should be used to bring the temperature back down to under 40F in less then 4 hours, as mentioned in Servesafe equirements to prevent food contamination. A cheap way to create an ice paddle is freeze a 2 liter soda bottle 3/4 filled with water (not recommended in institutional use). Or separate the stock into numerous small containers for quick cooling. If bubbles appear in a refrigerated stock dispose of it, it is contaminated.

Remouillage is French for rewetting, it means to use the bones and mirepoix again after it has already been used to make stock.

Glace is the term for a highly reduced stock and will have a cooled consistency of gelatin.

Commercial bases are a common way many places make their stocks or add stronger flavor to handmade stocks. I remember when reading Kitchen Confidential by Anthony Bourdain mentioning adding bouillion cubes to his stock in culinary school and no one understanding how he could get so much more flavor out of the bones. Some bases are highly reduced forms of stock, some are powders or cubes. Check the ingredients for any being used, some bases are very high in sodium and some contain few real base ingredients.

Basic Meat stock recipe: yield one gallon
8 lbs of bones and trimming
1 gallon cold water
1 lb mirepoix
1 bouquet garni

1. decide if you want white or brown stock
2. For brown stock lightly oil the pan, add bones and mirepoix to pan and roast at 425F for 30 minutes. (omit this step for white stock)
3. Place bones and mirepoix in stock pot of cold water, deglaze pan with water or red wine, bring pot to a light simmer.
4. Simmer the pot for 1 hour.
5. Skim, strain and cool