Ultimate Green Bean Casserole

This Ultimate Green Bean Casserole brings a fresh, homemade twist to a holiday favorite with crisp green beans, a rich mushroom sauce, and a golden crunchy topping that will brighten any festive gathering.

I first made this for a family dinner when canned casseroles felt too ordinary. Now everyone asks for this fresh version because it tastes so much better and looks stunning on the table.

Ingredients

• Fresh green beans: Bright color and tender crisp bite, pick beans that snap easily and have no blemishes
• Cremini or white mushrooms: Create a savory, umami packed sauce, choose firm mushrooms without slimy spots
• Garlic and shallots: Deepen flavor and aroma, fresher is always better for that punch of fragrance
• Butter and flour: Build a velvety, homemade roux that thickens the sauce harmoniously
• Whole milk or halfandhalf: For a smooth and creamy mouthfeel, full fat delivers the richest texture
• Chicken or vegetable broth: Adds savory balance, homemade or low sodium options work best to control saltiness
• French fried onions: Essential crispy topping, opt for good quality that stays crunchy even after baking

Instructions

Sauté the Aromatics:

Begin by cleaning and slicing mushrooms finely. Melt butter in a large skillet over medium heat and add mushrooms, minced garlic, and shallots. Cook gently for about 8 minutes until everything is soft and golden. This step releases deep, savory flavors crucial for the casserole’s richness.

Make the Roux:

Sprinkle flour evenly over the sautéed vegetables and cook for about 2 minutes while stirring constantly. This cooks out the raw flour taste and starts to thicken the sauce base.

Create the Mushroom Sauce:

Slowly pour in the milk and broth while whisking to avoid lumps. Continue to cook and whisk over medium heat until the sauce thickens and coats the back of a spoon, about 5 to 7 minutes. Season generously with salt, pepper, and a pinch of nutmeg to enhance the depth.

Blanch the Green Beans:

While the sauce thickens, bring a large pot of salted water to a boil. Trim and halve the green beans, then add them to the boiling water for 3 to 4 minutes until they turn bright green but still have a crisp bite. Immediately transfer them to a bowl of ice water to stop the cooking and preserve color.

Combine Beans and Sauce:

Drain the green beans and mix them gently into the mushroom sauce ensuring each bean is coated evenly. This step infuses the beans with the creamy, savory flavors.

Assemble the Casserole:

Preheat the oven to 375 degrees Fahrenheit. Butter a medium sized baking dish and pour in the green bean mixture, spreading it evenly.

Add Topping and Bake:

Generously sprinkle French fried onions over the top of the casserole. Bake uncovered for 20 to 25 minutes until the sauce bubbles and the onions turn golden brown and extra crunchy.

My favorite ingredient here has to be the cremini mushrooms. They bring that deep umami flavor that makes this casserole far from ordinary. I remember the first time I served this for Thanksgiving and the compliments poured in because it tasted so fresh, with real attention to detail.

Storage Tips

Leftovers keep well in an airtight container in the fridge for up to 3 days. To reheat, cover with foil and warm gently in a 350 degree oven until heated through to keep the topping crispy. Avoid microwaving as it softens the onions.

Ingredient Substitutions

You can swap halfandhalf for coconut milk for a dairy free version but expect a slightly lighter flavor. Use vegetable broth to keep the recipe vegetarian. If you can’t find French fried onions, crushed crispy shallots from the store also work well.

Serving Suggestions

This casserole pairs beautifully with roasted turkey or ham and a simple green salad. You can also turn it into a vegetarian main by adding cooked quinoa or lentils to the mix to make it more substantial.

Assemble the casserole ahead for easier holiday cooking and bake just before serving for the best texture. Your guests will love the fresh flavors and crunchy topping.

Your Recipe Questions Answered

→ What type of green beans work best?

Fresh green beans with tender-crisp texture are ideal to retain color and maintain a pleasant bite after baking.

→ Can I use other mushrooms besides cremini?

Yes, white mushrooms or any mild-flavored mushrooms work well to add savory umami notes to the sauce.

→ How do I make the mushroom sauce creamy?

Sauté mushrooms with garlic and shallots, then create a roux with butter and flour. Gradually whisk in milk and broth for smooth richness.

→ What is the purpose of blanching the green beans?

Blanching in salted boiling water brightens the beans’ color and preserves a tender-crisp texture before baking.

→ How do I achieve the crispy topping?

Scatter a generous layer of French fried onions on top just before baking; they become golden and crunchy in the oven.

→ Can this dish be made vegetarian?

Yes, substitute chicken broth with vegetable broth to keep it vegetarian while maintaining deep flavor.