Green Bean Casserole

Preheat oven to 475°F. Combine onions, flour, panko, and salt in a large mixing bowl and toss to combine. Coat a sheet pan with non-stick cooking spray and evenly spread the onions on the pan. Place the pan on the middle rack of the oven and bake until golden brown, approximately 30 minutes. Toss the onions 2-3 times during the cooking. Once done, remove from the oven and set aside until ready to use. Turn the oven down to 400°F.

While the onions are cooking, prepare the beans. Bring a gallon of water and 2 tbs. salt to a boil in an 8 quart sauce pan. Add beans and blanch for 5 minutes. Drain in a colander and immediately plunge beans in a large bowl of ice water to stop the cooking. Drain and set aside.

Melt the butter in a 12" cast iron skillet set over medium-high heat. Add the mushrooms, 1 tsp. salt, and pepper and cook, stirring occasionally until the mushrooms begin to give up some of their liquid, approximately 4-5 minutes. Add the garlic and nutmeg and continue cooking for another 1-2 minutes. Sprinkle the flour over the mixture and stir to combine. Cook for 1 minute. Add the broth and simmer for 1 minute. Decrease the heat to medium-low and add the half and half. Cook until the mixture thickens, stirring occasionally, approximately 6-8 minutes.

Remove from the heat and stir in ¼ of the onions and all of the green beans. Top with the remaining onions. Place into the oven and bake until bubbly, approximately 15 minutes. Remove and serve immediately.