With all of the great cancer-fighting compounds they contain, leeks certainly deserve more play time in recipes, especially during spring when they're in full abundance. As with other members of the onion family, slicing into fresh leeks unlocks the plant's store of pungent sulfur compounds and offers up cancer-fighting potential. Laboratory studies have shown that ingredients in onions can deactivate carcinogens and slow the growth of cancerous cells. Furthermore, studies have shown that people who regularly consume onions are at lower risk for certain types of cancer. To cash in on these health perks, sauté leeks as the base for a delicious soup, stew, or casserole, just as you would onions.