Delicate flavored leeks are cylindrical, leafy stalks and belong to the allium family as do garlic, onions, and shallots. Leeks contain many noteworthy flavonoid anti-oxidants, minerals, and vitamins that have proven health benefits.
Leeks impart a mellow, sweet oniony flavor to the dishes they added to. They give less pungency than garlic or onions.
Remove the thick green tops and cut away lower root end of the leek. Swish in a large bowl of water to shake out all grit and soil. Transfer to a colander to drain. Mop dry using paper towel. The outer layers generally peeled by hand. You may want to cut them into rings or slice.
Trim the green upper leaves off, trim roots off. With a sharp knife, make a vertical slice into the first outer layer and strip off that layer. Store the trimmed leeks in a plastic bag. They're all ready for use as onion in a recipe or for leeks in a recipe.
1 - 9 inch pie crust
Peel and slice potatoes thinly. Spread half the potato slices in a well-greased casserole. Slice the leeks thinly, and arrange over the potato layer. Cover with the remaining potato slices.
In a heavy saucepan, melt the butter. Blend in the flour. Stir in milk, and blend well. Bring to a boil, and remove from the heat. Add salt, pepper, and cheese, and mix well.
Pour evenly over the potatoes, cover tightly, and bake at 350 degrees for about 45 minutes. Remove cover, sprinkle with a little more grated cheese, dot with butter, and continue baking for about 15 minutes or until lightly browned.