Name: Creamy Green Bean Casserole with French Onions Recipe
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Cuisine: American
Ingredients: 2 pounds fresh or frozen green beans; 2 tablespoons unsalted butter; 2 tablespoons all-purpose flour; 1 teaspoon onion powder; 1 teaspoon garlic powder; 1 teaspoon sea salt; ½ teaspoon freshly cracked black pepper; ¼ teaspoon ground nutmeg; 1 teaspoon Dijon mustard; 1 cup vegetable or chicken stock; 2 cups half and half; 1 ½ cups French fried onions

There’s something about that perfect combination of creamy comfort and crispy topping that truly makes the Creamy Green Bean Casserole with French Onions Recipe a beloved classic on my table. It’s comfort food with a touch of elegance, and it always earns compliments no matter the occasion.

Creamy Green Bean Casserole - Recipe Image

Jump to:

Why You'll Love This Recipe
Ingredients & Why They Work
Make It Your Way
Step-by-Step: How I Make Creamy Green Bean Casserole with French Onions Recipe
Top Tip
How to Serve Creamy Green Bean Casserole with French Onions Recipe
Make Ahead and Storage
Frequently Asked Questions:
Final Thoughts
Creamy Green Bean Casserole with French Onions Recipe

Why You'll Love This Recipe

I’ve made this creamy green bean casserole countless times, and every single time it comes out just right—rich, flavorful, and perfectly textured. It’s one of those dishes that’s deceptively easy but delivers restaurant-quality results that impress family and guests alike.

Perfectly Balanced Creaminess: The sauce is velvety without being heavy, coating the green beans beautifully.
Textural Contrast: The crispy French fried onions on top add that much-needed crunch you’ll crave.
Simple Ingredients, Big Flavor: You don’t need fancy stuff—just common pantry staples that come together spectacularly.
Make-Ahead Friendly: It's a breeze to prep in advance and bake when guests arrive, cutting down your stress.

Ingredients & Why They Work

This recipe thrives because each ingredient plays a key role in creating that luscious, comforting flavor and texture we all love in a good green bean casserole. I always go fresh on the green beans when I can, but frozen works just fine and saves time without sacrificing taste.

Fresh or Frozen Green Beans: Fresh beans offer a crisp snap and vibrant flavor, but frozen is convenient and cooks quickly.
Unsalted Butter: It helps build the roux for the sauce’s creamy base and adds richness.
All-Purpose Flour: The thickening agent to give the sauce that silky texture without it being runny.
Onion Powder: Boosts that subtle onion flavor without chunks—perfect for smooth sauce.
Garlic Powder: Adds depth and a little savory warmth.
Sea Salt and Black Pepper: Essential for seasoning, bringing out all the flavors.
Ground Nutmeg: A secret hero, giving a touch of warmth and complexity.
Dijon Mustard: Just a little tang to brighten the creamy sauce and add an unexpected twist.
Vegetable or Chicken Stock: It’s the flavorful liquid that makes the sauce less heavy than cream alone.
Half and Half: Creates that luscious, creamy texture without being as rich as heavy cream.
French Fried Onions: The golden crunchy topping you can’t skip—adds a wonderful finish.

Note: Exact ingredients and measurements are listed in the recipe card below.

Make It Your Way

This casserole is super forgiving, so I encourage you to tweak it to your taste. Whether you like it a bit spicier or want to add extra veggies, it’s easy to make it your own—and honestly, that’s one of the joys of cooking it.

Variation: I sometimes add a handful of fresh mushrooms sautéed before mixing in the sauce, which adds a lovely earthy flavor that pairs well with the green beans and French onions.
Dairy-Free: Use a plant-based milk and dairy-free butter to keep creaminess without the dairy for those with intolerance.
Make It Vegan: Swap the half and half for coconut cream and use vegetable stock, then top with vegan fried onions.
Extra Crunch: Mix in some crushed toasted almonds or pecans with the fried onions on top for added texture diversity.

Step-by-Step: How I Make Creamy Green Bean Casserole with French Onions Recipe

Step 1: Blanching the Green Beans to Perfection

First off, bring a large pot of salted water to a roaring boil. Toss in your green beans and cook them just until they turn vibrant and are almost tender—about 3 minutes for fresh beans or 2 for frozen. Don’t overcook here; you want them to retain some snap. Then, quickly drain and plunge them into a big bowl of ice water to halt the cooking process. This keeps their gorgeous green color and makes sure they don’t get mushy later on. After chilling for a couple of minutes, drain thoroughly and pat dry so your casserole doesn’t get watery.

Step 2: Crafting the Lush Cream Sauce

Melt butter over medium-high heat in a large saucepan. Whisk in the flour, onion powder, garlic powder, salt, pepper, nutmeg, and Dijon mustard. This flavor-packed roux base cooks for about 2 minutes until it smells amazing and turns lightly golden. The mustard really gives it a nice punch that surprises you in a good way.

Next, slowly drizzle in the stock while whisking to keep it smooth, then the half and half, and bring everything to a gentle simmer. Cook for about 5 minutes, stirring frequently, until the sauce thickens into a silky, creamy coating that'll cling beautifully to your green beans.

Step 3: Combining and Baking

Spread the blanched green beans in a 9x13-inch baking dish. Pour the warm cream sauce over them and toss gently to ensure every bean is coated. Pop that dish into the preheated oven at 375°F and bake until you see the sauce bubbling happily, about 20 minutes.

Once bubbling, give the beans a gentle toss, then sprinkle a generous layer of French fried onions on top. Return it to the oven for another 10 minutes to brown those onions to golden crisp perfection. That crunchy top with creamy beans beneath? Total magic.

Top Tip

From years of making this, I’ve learned a few pro tips that make the difference between a good casserole and a truly standout one. Trust me, these little things really matter!

Don’t Skip the Ice Bath: It locks in the bright green color and keeps your beans perfectly firm.
Whisk Constantly: When making the sauce, keep whisking to avoid lumps and develop a smooth texture.
Butter Your Dish: Giving your casserole dish a lightly buttered spray or rub prevents sticking and helps clean-up.
Add Onions Just Before Baking: Don’t add the fried onions too early or they’ll get soggy—wait until the last 10 minutes.

How to Serve Creamy Green Bean Casserole with French Onions Recipe

Creamy Green Bean Casserole - Serving Suggestion

Garnishes

I like to finish this dish with a sprinkle of extra crispy French fried onions right before serving, sometimes adding a tiny pinch of fresh thyme or chopped parsley for a pop of green and fresh aroma. The fresh herbs brighten the creamy richness beautifully.

Side Dishes

This casserole is the perfect side for holiday feasts and everyday dinners alike. I often pair it with roast chicken or turkey, mashed potatoes, and a simple cranberry sauce or tangy salad to keep things balanced and fresh.

Creative Ways to Present

For special occasions, I’ve served this casserole in individual ramekins topped with a little extra fried onion and a sprig of rosemary. It feels more elevated and personal, plus it looks darling on the table!

Make Ahead and Storage

Storing Leftovers

Leftovers store beautifully in an airtight container in the fridge for up to 4 days. Before refrigerating, cool the casserole to room temperature, then cover tightly. When you’re ready to eat, just warm gently in the oven or microwave.

Freezing

I’ve frozen this casserole successfully too! Freeze it before baking, tightly wrapped and sealed to prevent freezer burn. When thawed overnight in the fridge, you can bake it straight from cold, just add a few extra minutes to the cooking time.

Reheating

To reheat, I prefer the oven to keep the sauce creamy and the topping crisp. Cover loosely with foil and heat at 350°F until warmed through, then uncover for the last 5 minutes to refresh the crunch.

Frequently Asked Questions:

Can I use canned green beans instead of fresh or frozen?

Canned green beans tend to be too soft and watery for this casserole, so I recommend sticking with fresh or frozen for the best texture and flavor.

Why is Dijon mustard used in the recipe?

Dijon mustard adds a subtle tang and depth of flavor that balances the richness of the cream sauce without making the dish taste like mustard. It’s a little trick I’ve grown to love over the years.

How do you keep the French fried onions crispy?

Add the French fried onions on top of the casserole only during the last 10 minutes of baking to keep them from sogging up, and serve soon after baking for maximum crunch.

Can this recipe be made vegan?

Yes! Replace the half and half with coconut cream or a thick plant-based milk, use vegetable stock, and swap the butter for a vegan alternative. Make sure to find vegan-friendly French fried onions or make your own crispy topping.

Final Thoughts

Honestly, this Creamy Green Bean Casserole with French Onions Recipe has been a staple at my family dinners for years. It’s the kind of dish that feels like a warm hug on a plate and brings people together instantly. I hope you give it a try and make it your own—because at the end of the day, that’s what great recipes are for.