Creamy Potatoes with Eggplant and Cheese

Steve and I made this from the Mark Bittman cookbook a few weeks ago. We found this recipe in search of something to do with the potatoes we purchased for a different meal. It's actually a variation on a Greek dish, called pastitsio, usually made with pasta instead of potatoes. It turned out to be really, really delicious, but a bit time-consuming to make. We started making it late and ended up eating around 10'o'clock. Don't let the time of preparation scare you, though. This is seriously one of the tastiest things we've made.

Ingredients
2 tablespoons olive oil, plus more as needed
1 lb. eggplant, peeled and cut into 1-inch cubes
salt and freshly ground black pepper
1 small red onion, chopped
1 tablespoon minced garlic
1/4 teaspoon each ground cinnamon and cloves
cayenne or hot red pepper flakes to taste
2 cups chopped tomato (canned are fine)
4 tablespoons butter
1 lb. all purpose potatoes, washed, peeled, and cut into cubes
2 tablespoons breadcrumbs
1 1/2 cups milk
2 tablespoons all purpose flour
pinch of nutmeg
2 eggs, beaten
1 cup Parmesan

Put olive oil in a large, deep skillet over medium-high heat. When hot, add the eggplant, sprinkle with salt and pepper, and cook, stirring occasionally and adding a little more oil if necessary, until the eggplant it softened and browned all over, about 5 minutes. Remove with a slotted spoon. Add more oil to the pan if needed to coat the bottom and return it to the heat. Add the onion and garlic and cook, stirring occasionally, until soft, about 2 minutes. Turn the heat down to medium-low and cook, stirring occasionally, until the sauce thickens, about 10 minutes. Return the eggplant to the pan, taste and adjust the seasoning, then set aside. Put potatoes in a large pot, fill with cold water, and salt it. Boil the potatoes until softened, drain. Put the potatoes into a large bowl and toss with 1 tablespoon of the melted butter and 1 tablespoon of the breadcrumbs. Use some butter to grease a baking dish.

In a small saucepan or microwave, heat the milk until small bubbles appear. Reheat the remaining butter over medium-low heat in its saucepan. Add the flour to the melted butter and stir almost constantly with a wire whisk until the mixture turns golden, about 5 minutes. Slowly add the milk, whisking constantly; cook, whisking, until the mixture thickens, 3 to 5 minutes. Add the nutmeg and sprinkle with salt and pepper.

Stir a couple of tablespoons of the hot sauce mixture into the beaten eggs, then a little more. Pour this mixture back into the sauce and stir. Add most of the Parmesan and stir again.
Put half the potatoes in the baking dish; cover with half the eggplant mixture. Cover with the remaining potatoes, then the remaining eggplant and all the cheese sauce. Sprinkle with the remaining Parmesan and the remaining breadcrumbs. Bake for about 45 minutes, until top turns golden brown. Let rest for a few minutes before cutting and serving.