Kabocha Squash Mac 'n' Cheese with Pork Rind Crust

Preheat the oven to 375 degrees F. Butter a 4-inch-deep 9-by-12-inch baking dish or casserole. 2. Peel and halve the squash. Scrape out the seeds and membranes and cut into rough 1-inch cubes. Place them on a baking sheet, toss with the olive oil, and season with a little salt and pepper. Spread them out on the baking sheet and bake for about 25 minutes, or until the squash is fork-tender. 3. Meanwhile, bring a large pot of lightly salted water to a boil. Add the elbow macaroni and cook for 8 to 10 minutes, or until cooked but still with a slight resistance to it. Drain the macaroni in a colander and cool under cold running water. Set aside. 4. Transfer the cooked squash to a blender, add the milk, chicken stock, three cheeses, and the butter, and blend on high to a smooth puree. Add 2 teaspoons salt, 3/4 teaspoon pepper, and the nutmeg and pulse to mix. Transfer the squash puree to a bowl, add the elbow macaroni, and mix thoroughly. 5. Transfer the mixture to the buttered baking dish. Sprinkle the pork rinds and sesame seeds over the top. Cover with foil and bake for 20 minutes. 6. Remove the foil, and continue baking until the mac 'n' cheese is lightly browned and crisp on top, another 25 to 30 minutes.