The humble leek is a gentler and more mild cousin of your standard onion, and pairs great with both delicate and hearty veggies. Caramelized leeks get less recognition than their onion-y counterparts, but are truly delicious. You actually can eat most of the the greens if you want - just make sure to cut them really fine and cook long enough to make them tender (quite a bit longer than you'll need to cook the whites). The greens also impart amazing flavor into stocks, stews, and beans - you can just put them in whole and fish them out before serving.
Grown by Rainshadow Organics in Sisters.