Butternut Squash and Duxelles Casserole
Duxelles (pronounced dook-SEHL) is a paste of finely chopped mushrooms and shallots used to flavor classic French dishes. A food processor makes quick work of the chopping. The mixture is extremely versatile—try it spread on toast as an appetizer. This recipe is also a good way to use tough stems from shiitake and portobello mushrooms.
1. Pulse mushrooms in food processor 20 times, or until finely chopped. Transfer to bowl. Place shallots in food processor; pulse 20 times, or until finely chopped. Transfer to same bowl.
2. Melt butter in skillet over medium-high heat. Add mushrooms and shallots, and season with salt, if desired. Cook 10 minutes, or until mushrooms have released their liquid, most liquid has evaporated, and shallots are lightly browned, stirring occasionally. Stir in parsley and pepper.
3. Preheat oven to 350°F. Coat 9-inch deep-dish pie pan or gratin dish with cooking spray.
4. Bring milk, flour, and garlic to a simmer in saucepan over medium heat, whisking constantly. Cook 2 minutes, or until sauce is thick enough to coat back of spoon, whisking frequently. Whisk in 1/2 cup cheese and nutmeg, and season with salt and pepper, if desired.
5. Spread one-third squash in prepared pan. Top with 1/3 cup cheese sauce and half of mushroom mixture. Repeat layers, ending with cheese sauce. Sprinkle with remaining 1/4 cup cheese. Bake 45 minutes, or until squash is tender and top is browned. Let stand 10 minutes before serving.