Don't Miss: 13 Easy Ways to Jazz Up Green Bean Casserole
- 1 lb. fresh green beans, washed and trimmed
- 4 Tbsp. butter, divided
- 8 oz. mushrooms, sliced
- 2 cloves garlic, minced
- kosher salt and freshly-ground black pepper, to taste
- 2 Tbsp. all-purpose flour
- 2 cups whole milk, half and half, or cream
- 1 Tbsp. Dijon mustard
- 1/2 cup grated Parmesan cheese
- 1 cup crispy onion strips (such as Fresh Gourmet)
- Preheat oven to 375 degrees F. Spray a 1-1/2 quart baking dish with cooking spray.
- Place green beans in a gallon-size resealable plastic bag. Poke a few holes in the bag to allow steam to escape. Heat in the microwave on full power for 3-5 minutes until beans are tender, but still a bit crisp. Pour into prepared pan.
- Heat two tablespoons of the butter in a small frying pan. Add mushrooms, garlic, salt and pepper. Cook, stirring occasionally, until most of the liquid from the mushrooms has evaporated. Pour over green beans. Toss.
- Heat remaining two tablespoons of butter in a small saucepan over medium heat. Whisk in flour. Cook 1-2 minutes until flour starts to turn golden.
- Slowly add milk or cream. Stirring constantly, cook until mixture starts to bubble and thicken. Add salt, pepper, Dijon mustard and Parmesan cheese. Pour over mushrooms and green beans.
- Bake 15-20 minutes until bubbly. Sprinkle crispy onions on top. Bake another 5 minutes.
- Let green bean casserole rest 5-10 minutes before serving.