Put any fresh vegetables in season in a large stewpot - being careful not to include overmuch cabbage or other coarse green leaves, as these give a rather strong flavour - with a quart or more of water, cover, and simmer gently for at least two hours. The outer leaves discarded when preparing vegetables for the table, the stalks and stems, and the peelings of apples, potatoes, etc., should all be used for stock, care being taken, of course, to cleanse them well first, cutting out any insect-eaten or decayed parts.