Preheat the oven to 375°. Butter an 8-inch square (1 1/2 quart) baking dish or pan (or six 8-ounce ramekins). Set aside. Fill a 4- to 5- quart pot three-quarters full of water and bring to a boil. Add 1 tablespoon salt and the pasta and cook, stirring once or twice, until tender but firm, 4 to 6 minutes, and drain. Reserve the pot.
In a medium skillet, cook the bacon until crisp. Drain on a paper towel–lined plate. Pour off all but 1 tablespoon fat and add the leeks. Cook over medium heat until soft but not brown, about 5 minutes. Sprinkle with salt and pepper, to taste.
In a large bowl, whisk together the eggs, milk, crème fraîche, 1 teaspoon salt, pepper and nutmeg. Add the pasta, 2 1/2 cups of Dubliner® Cheese and the leeks and bacon. Stir to combine. Pour into the prepared baking dish. Sprinkle with the remaining Dubliner® Cheese. Place dish on a rimmed baking sheet and bake until bubbling and golden brown, about 30 minutes. Let cool for 15 minutes before serving.