A perfect holiday side dish with fresh ingredients! Made with delicious Highline Mini Bella mushrooms, fresh green beans and crispy crunchy fried onions.
Preheat the oven to 375ºF. In a large pot, boil the green beans in salted water for 3-5 minutes until tender yet crisp. You may have to do this in batches. Drain then transfer them to a 13×9 baking dish. Set aside.
In a large skillet, heat olive oil and 2 tablespoons of butter at medium heat. Add the mushrooms and cook until golden brown about 4-5 minutes. Transfer to a plate. Set aside.
In the same skillet, heat remaining butter at medium heat. Once melted, whisk in flour to form a roux, about 2-3 minutes. Whisk in the milk and cream. Stir in smoked paprika, garlic powder, thyme sprigs, salt and pepper to taste. Cook for 3-5 minutes until the sauce thickens.
Add the mushrooms back in and stir to combine with the sauce. Simmer for 1-2 minutes. Taste and adjust seasonings as needed. Pour the mixture over the green beans in the baking dish.
Cover the baking dish tightly with aluminum foil. Bake for 25-30 minutes then remove the baking dish from the oven, remove the foil, and then bake uncovered for another 10 minutes. Top the casserole with fried onions. Serve and enjoy!