Marrow comes from inside the hollow centre of animal bones. It is normally taken from leg or shin bones of beef or veal.
Marrow is a soft, fatty tissue that can be red or yellow.
Red marrow produces blood cells and stem cells in an animal. It is found in ribs, skulls, spines, and breast, collar and pelvic bones.
Yellow marrow comes mostly from arm and leg bones. It is largely fat.
Either kind has a rich flavour and soft texture.
This is completely different from the vegetable called Marrow.
Marrow can be cooked in the bone or removed and cooked separately.
To get marrow out, you have to split the bone in half or get the bone cut into small segments or split open for you by the butcher.
Ideally, you try to extricate the marrow all in one piece if you can. You cut it out with a sharp knife, then slice or cube it.
Marrow can be roasted or used for stock. It is also good to flavour soups with.
Slices and cubes can be gently simmered for use as a garnish or on canapés. It is often used as a garnish in classical French cooking.
You can also cook it right in the bone by tossing it into a soup, and then when done, spoon it out.