Nature's Beauty. Leeks

You might walk past leeks in the produce section, but I'd consider adding them to your list. Use them as you would onions, scallions, shallots or garlic. Slice thin, and soak in a bowl of water to remove any dirt or residue before cooking.
I enjoy roasting a whole chicken or tri-tip roast with lots of vegatables and leeks, as well as adding to homemade soups or stock. Try it.