Green Bean, Mustard & Mushroom Casserole

A modern take on the classic — fresh beans, real cream, a touch of Dijon, and that savory crunch on top.

Serves: 6
Prep time: 15 minutes
Cook time: 25 minutes

Ingredients

• 1 ½ pounds fresh green beans, trimmed
• 2 tablespoons butter
• 1 tablespoon olive oil
• 1 medium onion, finely diced
• 2 garlic cloves, minced
• 8 ounces mushrooms, sliced (cremini or button)
• 2 tablespoons flour
• 1 cup chicken or vegetable stock
• 1 cup whipping cream (or half-and-half for lighter version)
• 1 teaspoon Dijon mustard
• Salt and freshly ground black pepper, to taste
• 1 cup store-bought fried onions, for topping

Instructions

1. Preheat the oven to 400°F.
2. Cook the green beans:
   Place green beans in a microwave-safe dish and cook in 8-ounce batches for 3–4 minutes each, depending on your microwave’s power. They should be bright green and slightly al dente — they’ll continue to cook later in the sauce. Drain and set aside.
3. Make the sauce:
   In a large skillet or saucepan, melt the butter with olive oil over medium heat. Add onion and sauté until translucent, about 3 minutes. Add garlic and mushrooms and cook until mushrooms release moisture and start to brown, 5–6 minutes.
4. Thicken the sauce:
   Sprinkle flour over the mixture and stir for 30 seconds. Slowly whisk in the stock until smooth. Stir in the cream and Dijon mustard; simmer until thickened (about 3 minutes). Season with salt and pepper.
5. Combine:
   Add the cooked green beans to the sauce and stir gently to coat evenly.
6. Bake:
   Transfer to a baking dish, top with fried onions, and bake uncovered for 10–15 minutes or until bubbling and golden on top.

To Serve

Let rest for 5 minutes before serving. Garnish with a sprinkle of fresh thyme or parsley for color and a hint of freshness.

Nutrition & Culinary Medicine Notes

This updated casserole skips the canned soup and relies on fresh mushrooms, which provide ergothioneine — a natural antioxidant that supports brain and heart health. The Dijon mustard deepens flavor without extra sodium, and the olive oil–butter combination adds the right balance of richness and Mediterranean tradition.

Mediterranean Diet Points

1 point for legumes (green beans).

Nutritional Information (per serving)

• Calories: ~210
• Total Fat: 15g
• Saturated Fat: 8g
• Cholesterol: 35mg
• Sodium: 310mg
• Carbohydrates: 15g
• Dietary Fiber: 3g
• Sugar: 5g
• Protein: 5g

This dish brings together American comfort and Mediterranean balance — creamy, crisp, and evidence-based delicious.