Name: Green Bean Gratin
Prep time: 10 min
Cook time: 30 min
Total time: 40 min
Ingredients: 1 lb Green beans, trimmed and rinsed; 1 can (10.75 oz) Cream of mushroom soup (Room temperature); 1 cup French fried onions (Divided (1/2 cup for mixing, 1/2 cup for topping)); 1 cup Shredded cheddar cheese (Divided (1/2 cup for mixing, 1/2 cup for topping)); 1/2 teaspoon Garlic powder; 1/4 cup Milk (Room temperature (whole or 2% recommended)); to taste Salt (Start with 1/4 teaspoon); to taste Black pepper (Start with 1/4 teaspoon)

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Creamy, crunchy, and utterly comforting — this Green Bean Gratin is the kind of side dish that steals the spotlight at weeknight dinners and holiday tables alike. With tender green beans folded into a rich mushroom-soup sauce, topped with melty cheddar and crispy French-fried onions, it’s simple to make and impossible not to love. Fun fact: many families claim the crunchy onion topping is the “crowd whisperer” that gets even picky eaters to ask for seconds. If you love green bean classics, this one sits proudly next to favorites; in fact, if you enjoy our best green bean casserole, you’ll find this gratin an easy, slightly elevated cousin with extra texture and cheesy comfort. Read on — you’re going to want to make this tonight.

What is Green Bean Gratin?

What’s in a name? A gratin is simply a dish finished with a golden, crispy top — so “Green Bean Gratin” essentially promises velvet beans under a crunchy blanket. Curious where the term came from? Picture a French casserole pan and a proud home cook sliding a bubbling pan from the oven — voilà. Is it fancy or homey? Both. And who can resist a recipe that makes you smile when it comes out of the oven? After all, “the way to a man’s heart is through his stomach.” Give it a try and see who in your house falls in love first.

Why You’ll Love This:

Creamy-cheesy comfort with a crispy finish: The savory mushroom soup base and cheddar create a luscious sauce that clings to every bean, while the French-fried onions add a crunchy contrast that makes each bite exciting.
Budget-friendly and family-approved: Pantry-friendly ingredients like canned soup and frozen or fresh green beans keep cost low while delivering big flavor — perfect for weeknight dinners or potlucks.
Versatile and flavorful toppings: Swap the cheddar for Gruyère or add a pinch of smoked paprika for a smoky twist; it’s a simple canvas that highlights fresh or frozen green beans beautifully.

If you enjoy hearty, bacon-forward sides, you might also like the twist on green beans and potatoes we’ve featured elsewhere — try the country ranch green beans and potatoes with bacon for another crowd-pleasing option. Ready to bake? Let’s get to it.

How to Make:

Quick Overview

This Green Bean Gratin is a no-fuss, weeknight-friendly dish that comes together quickly: mix, top, and bake. Preparation is straightforward — a simple toss of green beans with soup, milk, and seasonings, a sprinkle of cheese, and about 25–30 minutes in a hot oven to get bubbly and golden. The standout is the contrast between the creamy center and the crisp onion topping, giving you both comfort and crunch in every forkful. Prep time is about 10 minutes, and cook time around 25–30 minutes, so total time is under 45 minutes.

Ingredients

1 lb green beans, trimmed and ends removed, rinsed and patted dry
1 can (10.75 oz) cream of mushroom soup, room temperature
1 cup French fried onions, divided (half for mixing, half for topping)
1 cup shredded cheddar cheese, divided (1/2 cup for mixing, 1/2 cup for topping)
1/2 teaspoon garlic powder
Salt and black pepper to taste (start with 1/4 teaspoon each)
1/4 cup milk, room temperature (use whole milk or 2% for best creaminess)

Directions

Preheat your oven to 375°F (190°C). Lightly grease a 1.5- to 2-quart baking dish with butter or nonstick spray.
If using fresh green beans, trim the ends and rinse them. If using frozen green beans, thaw and drain thoroughly so the gratin doesn’t get watery.
In a large mixing bowl, combine the cream of mushroom soup and milk. Whisk until smooth and pourable. Stir in the garlic powder, a pinch of salt, and a few grinds of black pepper.
Add the green beans to the bowl and toss to coat evenly in the soup mixture. Fold in half of the shredded cheddar cheese and half of the French fried onions so they’re distributed throughout the beans.
Transfer the coated green beans into the prepared baking dish, spreading them into an even layer. Sprinkle the remaining cheddar cheese over the top, then scatter the remaining French fried onions evenly to form a crunchy crust.
Bake uncovered in the preheated oven for 25 to 30 minutes, or until the gratin is bubbly around the edges and the topping is golden brown. If you’d like the onions extra-crisp, place the dish under the broiler for 1 minute, watching carefully to avoid burning.
Remove from oven and let the gratin rest for 5 minutes before serving — this helps the sauce set slightly so it won’t run off the beans.

Green Bean Gratin

What to Serve With:

Roasted or grilled chicken for a classic pairing (the creamy gratin complements simply seasoned poultry).
Sliced roasted ham or baked pork chops for a holiday-style plate.
A crisp green salad with vinaigrette to cut through the richness.
Warm dinner rolls or crusty bread to soak up any extra sauce.
For drinks, a light white wine like Sauvignon Blanc or a sparkling water with lemon brightens the meal.

Top Tips for Perfecting:

Use fresh or properly thawed frozen beans: Fresh beans give the best texture; if using frozen, squeeze out extra moisture with paper towels.
Cheese choices: Sharp cheddar gives bold flavor; Gruyère or a mix of cheddar and Parmesan adds nuttiness.
Onion topping timing: Stir some onions into the mix for interior crunch, and reserve some for a final golden topping. Add the topping later if you want it crisper.
Season carefully: Canned soup can be salty; taste the mixture before adding more salt. Start with a small pinch and adjust.
Avoid sogginess: Ensure the milk and soup are well combined and the beans aren’t waterlogged. Pat frozen beans dry and drain well if parboiled.

Storing and Reheating Tips:

Refrigeration: Store leftovers in an airtight container in the fridge for up to 3 days. Reheat in a 350°F (175°C) oven for 10–15 minutes until warmed through to preserve texture.
Freezing: You can freeze the unbaked gratin (without topping) for up to 2 months. Thaw overnight in the refrigerator before adding toppings and baking. Avoid freezing once fully baked; the topping will become soggy on thawing.
Microwave reheating: For single servings, microwave on medium power in 30-second bursts, stirring between intervals; then finish in a hot oven or under the broiler for 1 minute to re-crisp the topping.

FAQs

Can I use frozen green beans?
Yes. Thaw them completely and pat dry before mixing to prevent a watery gratin. If they’re frozen solid, briefly steam or microwave and drain well.

Is there a substitute for cream of mushroom soup?
Absolutely. Mix 1 cup of milk with 1 tablespoon butter and 1 tablespoon flour cooked into a roux, then whisk in a splash of chicken or vegetable stock and a pinch of salt for a homemade white sauce.

Can I make this ahead for a holiday meal?
Yes — assemble the gratin, cover, and refrigerate up to 24 hours before baking. Add the crunchy topping just before baking for best texture.

How can I make this gluten-free?
Use a gluten-free condensed cream soup (or make a gluten-free roux), and swap the French fried onions for gluten-free crispy onions or crushed gluten-free crackers.

Can I add extra vegetables or bacon?
Certainly. Cooked mushrooms, sauteed onions, or crumbled cooked bacon folded into the mix all make delicious additions — adjust salt accordingly.

Conclusion

This Green Bean Gratin is a cozy, crowd-pleasing dish that’s quick enough for weeknights and pretty enough for special occasions — creamy, cheesy, and topped with irresistible crunch. It’s budget-friendly, forgiving for cooks of all levels, and endlessly adaptable to what you have on hand. If you want to see another version of this classic, check out this Green Bean Gratin for more inspiration. Make a batch, share it, and enjoy the smiles at the table.