This was adapted from Margaret Johnson's cookbook, The New Irish Table. Her note from this recipe is as follows: "Related to both onion and garlic, leeks look like giant scallions but are the mildest of all of the three. Leeks figure prominently in recipes of Celtic nations from the earliest times, especially as a flavoring in soups or stews. They are often served as a side dish, as in this gratin from Marigold Allen, hostess of the Beeches Country House, County Antrim."
To Make Fresh Seasoned Bread Crumbs: Place cubed baguette and herbs/seasonings in a blender or food processor. Process for 15-20 seconds, or until mixture is finely ground. Set aside. Makes about 1 cup
To Make Leeks: Preheat oven to 350 deg F. Butter an ovenproof casserole dish.
Cut leek halves into 6" pieces. Rinse well under cold running water to remove all sand and grit. Cook for 5 minutes in salted boiling water, or until slightly tender. Drain.
Put the precooked leeks in the buttered dish, cut side up. Pour in the heavy cream. Evenly sprinkle the cheese, salt and pepper over the leeks.
Bake for 10-15 minutes in preheated oven, or until the cream has thickened and cheese has melted.
Remove from the oven and preheat the broiler. Sprinkle the prepared bread crumbs over the leeks. Broil dish 4" from the heat for 2-3 minutes, or until lightly browned. Serve.