Allium Porrum: A mild onion-like taste, less bitter than a scallion. A member of the garlic family.
The edible portion is the white bulb area and the lighter green sections. The very dark green is usually discarded.
I love to keep Leeks on hand all the time. I use them in cooking, on salads and sandwiches. They keep a lot longer than scallions.
Leeks tend to get very very sandy. The sand collects deep inside and is hard to just rinse off.
To clean I cut them in half length wise. Cut off the very dark greens, leaving them long enough to fit into a large zip lock bag.
Take the half's and rinse under cold running water in the sink. Separating the leaves as you rinse gently to remove the unwanted sand.
I prefer this method so it keeps longer.
You can also just chop up the leek and toss into a bowl of cold water, swish around and then drain in a strainer. The sand will fall to the bottom of the bowl.
Place into plastic bag and put in the fridge. The leek is cleaned and ready to use when ever you need it.