We have a big herb garden (chives, parsley, basil, mint, thyme, and oregano) that grows well, doesn't take up much space, freezes well, and costs a fortune if you have to buy them in the store, so they're my favorite
We also have tomatoes, cucumbers, peas, string beans, spinach, and eggplant, though the only thing we have a lot of success with are the string beans. Hopefully this summer will be better...