Creamy Cabbage Casserole

Preheat oven to 350°F. Coat an 8-inch-square baking dish with cooking spray. Melt 2 tablespoons butter in a large Dutch oven over medium-high heat. Add cabbage, onion and celery; stir to coat well. Cover and cook, stirring occasionally, until the cabbage is tender-crisp, 15 to 18 minutes.

Meanwhile, place the remaining 1 tablespoon butter in a small microwaveable bowl; microwave on High until melted, about 20 seconds. Add crackers to the butter and toss together until combined.

Sprinkle the cabbage mixture evenly with flour and stir to coat. Stir in milk and bring to a simmer over medium-high heat. Simmer, uncovered, stirring often, until the sauce is thickened and creamy and coats the cabbage mixture, 2 to 3 minutes. Add mustard, salt, cayenne, nutmeg and 1/2 cup cheese; stir until the cheese melts, about 30 seconds.

Spoon the cabbage mixture into the prepared baking dish. Sprinkle evenly with the remaining 1/2 cup cheese and the buttered cracker mixture. Bake until bubbly around the edges and golden brown on top, about 20 minutes. Let stand for 5 minutes before serving.