It's easy to grow your own tasty onions when you start by planting onion sets. 'Sets' are tiny onions grown from seed which when replanted in spring just carry on growing, giving delicious bulb nions which are ready for lifting in early autumn. It works perfectly and is the chosen method of most professional growers.
Stuttgart Giant is a trusted garden variety which produces a heavy crop of flattish brown skinned bulbs which have a great taste and are easy to prepare in the kitchen. Lift and dry and then keep in a cool airy place and they will store well indoors until well after Christmas.