Main Courses
This Campbell's string bean casserole recipe brings back the comforting flavors of classic American home cooking that my Nonna used to make. The creamy, cheesy goodness in one dish is exactly what makes this recipe a timeless favorite for family dinners.
I've tested it countless times to ensure it delivers that perfect balance of tender string beans, rich creaminess, and melted cheese that everyone loves.
The beauty of this recipe lies in its simplicity—just a few pantry staples come together in one baking dish for a meal that's both comforting and satisfying.
You'll need Campbell's cream of mushroom soup, green string beans, milk, and a blend of cheddar and mozzarella cheeses, all combined and baked until bubbly and golden. The result is a dish that's hearty enough to serve as a main course but easy enough to prepare on a busy weeknight.
What makes this casserole truly special is how it transforms simple ingredients into something deeply comforting. The string beans stay tender while the cheese melts into a velvety sauce that coats every bite, creating a texture that's both creamy and satisfying.
It's the kind of dish that tastes even better the next day, making it perfect for meal prep or feeding a crowd.
Serve it warm with crusty bread or over a bed of rice to soak up every last bit of that rich, cheesy goodness. Here's how to make this classic Campbell's string bean casserole that's sure to become a family favorite.
Ingredients for campbell's string bean casserole
Classic comfort food with just a few essential pantry staples and cheeses.
| Ingredient | Amount | Notes |
|---|---|---|
| Campbell's Cream of Mushroom Soup 🍄 | 2 cans | Condensed, 10.5 oz each |
| Green String Beans 🌱 | 2 lbs | Fresh or frozen, trimmed |
| Whole Milk 🥛 | 1 cup | Full-fat preferred |
| Sharp Cheddar Cheese 🧀 | 1 ½ cups | Shredded, block preferred |
| Mozzarella Cheese 🧀 | 1 cup | Shredded, part-skim or whole |
| Yellow Onion 🧅 | 1 medium | Diced, about 1 cup |
| Garlic Cloves 🧄 | 3 cloves | Minced, fresh preferred |
| All-Purpose Flour 🌾 | 2 tbsp | For thickening sauce |
| Salt 🧂 | 1 tsp | Kosher or sea salt |
| Black Pepper 🌶️ | ½ tsp | Freshly ground preferred |
| Butter 🧈 | 2 tbsp | Unsalted, melted |
| Breadcrumbs 🍞 | ½ cup | Plain or panko style |
The Campbell's cream of mushroom soup is the foundation of this casserole—stick with the classic, not the low-fat version. For the string beans, fresh is ideal, but frozen works perfectly if you're short on time. Trim the ends and blanch them for 2 minutes to keep them vibrant. The cheeses are where the magic happens: sharp cheddar for that tangy bite and mozzarella for the melt. Grab pre-shredded if you're in a hurry, but freshly grated stays creamier. Yellow onions add sweetness—sweet Vidalia onions if you want to splurge, but regular yellow works fine. The garlic should be fresh, not that jarred minced stuff.
No Campbell's soup? Homemade mushroom cream sauce works—simmer mushrooms, garlic, and cream with a splash of milk. Short on string beans? Green beans or broccoli are great swaps, but keep the quantity similar. If you don't have mozzarella, add extra cheddar and a splash of milk to compensate. The breadcrumbs can be panko for extra crunch or regular for a softer topping. For a dairy-free option, use nutritional yeast and skip the milk in the sauce. The butter is key for richness—don't skip it if you want that classic texture.
This casserole tastes even better the next day—double the batch and freeze half for a lazy dinner. Store leftovers in an airtight container for up to 5 days in the fridge. For the freezer, portion into individual servings and reheat covered with foil until bubbly. The topping stays crispy if you broil it for 2-3 minutes at the end. Serve with crusty bread or rice to soak up every last bit of that creamy goodness.
Why You'll Love This Recipe
- One-Pot Magic: I swear by this recipe when I’m too tired to wash a million dishes. Just toss the beans, soup, and milk in one pan, top with cheese, and bake—no chopping, no fuss. The only tool you’ll need is a spatula, and honestly? That’s my kind of cooking.
- Creamy Cheesy Bliss: Between us, the combo of sharp cheddar and mozzarella on top of that mushroom soup base is ridiculously good. The cheese melts into a golden blanket while the beans stay tender—no dry, sad casserole here. It’s the kind of dish that makes people ask, “What’s in this?” before taking seconds.
- Potluck Star: This is my go-to for church dinners, family gatherings, or when my book club shows up unannounced. It travels well, reheats perfectly, and even my picky teenage nephew won’t complain. Plus, the creamy texture holds up better than most casseroles when you’re passing it around a crowded table.
- Budget-Friendly Leftovers: I make this on Sundays because it stretches across lunches and dinners without getting boring. The Campbell’s soup keeps costs low, and the cheese stretch goes a long way. Best part? The flavor only gets better the next day—proof that good food doesn’t have to break the bank.
Step-by-step instructions for Campbell's string bean casserole
Here's how to assemble this cheesy, creamy classic with perfect texture and rich flavor.
Prepare the String Beans and Aromatics
Trim the ends from the 2 lbs of green string beans and cut them into 2-inch pieces. If using fresh beans, blanch them in boiling water for 3 minutes, then drain and rinse with cold water to stop the cooking process. This ensures they stay crisp-tender in the casserole.
While the beans cool, dice the 1 medium yellow onion into ¼-inch pieces and mince the 3 cloves of garlic. Set both aside in separate bowls. The onion should yield about 1 cup when diced, which is the perfect amount for this recipe. Fresh garlic adds a bright, aromatic depth that canned garlic simply can't match.
Create the Creamy Sauce Base
In a large mixing bowl, combine the 2 cans of Campbell's Cream of Mushroom Soup, 1 cup of whole milk, and the 2 tbsp of all-purpose flour. Whisk everything together until smooth and fully incorporated. The flour will help thicken the sauce as it bakes, creating that perfect creamy consistency.
Next, stir in the diced yellow onion, minced garlic, 1.5 cups of sharp cheddar cheese, and 1 cup of mozzarella cheese. Mix until the cheese is evenly distributed throughout the sauce. You want the cheese to melt completely during baking, so make sure it's well combined now. If you notice any large cheese clumps, press them through a fine-mesh strainer to ensure a silky texture.
Combine with String Beans and Season
Add the prepared string beans to the cheese sauce mixture and gently fold everything together. Sprinkle with 1 tsp of salt and 0.5 tsp of black pepper, then mix again to ensure even seasoning. The beans should be fully coated in the creamy mixture, but be careful not to overmix or they may break into smaller pieces.
Transfer the entire mixture to a greased 9x13-inch baking dish. The dish should be about three-quarters full. Smooth the top with a spatula, creating an even layer. This even distribution ensures the casserole cooks uniformly and has a consistent texture throughout.
Top with Breadcrumbs and Bake
Melt the 2 tbsp of butter in a small saucepan over low heat, then stir in the 0.5 cup of breadcrumbs. Spread this buttery breadcrumb mixture evenly over the top of the casserole. The breadcrumbs will create a golden, crispy crust while absorbing some of the creamy sauce, adding texture contrast.
Bake the casserole uncovered at 350°F for 45-50 minutes, until the top is golden brown and the edges are bubbling. The center should be hot to the touch, indicating the filling is fully cooked through. If the top browns too quickly, tent it loosely with aluminum foil for the last 10 minutes of baking to prevent over-browning.
Rest and Serve
Remove the casserole from the oven and let it rest for 10-15 minutes before serving. This resting period allows the filling to set slightly, making it easier to slice and serve. The breadcrumb topping will be crispy on the outside while still maintaining a slightly soft texture underneath.
Cut into 6 equal portions and serve warm. Each serving should have a creamy, cheesy filling with tender string beans and a crispy breadcrumb topping. The flavors will meld beautifully as it cools slightly, making this a comforting classic that's perfect for family meals or potlucks.
Pro Tips For Making Campbell'S String Bean Casserole
- STEAM BEANS FIRST: Dump those string beans straight into boiling water for 3-4 minutes before draining. I learned this the hard way—raw beans in the casserole turn mushy and sad, while pre-steamed ones hold their shape and stay crisp-tender. Use a colander, not the sink strainer, or you’ll lose half your beans to the abyss.
- SALT THE MILK: Add a pinch of salt to the whole milk before mixing it with the soup. The cheese melts smoother and the flavor’s more balanced—no need to over-salt later. (Yes, even if you’re impatient like me, let it sit for 30 seconds so the salt dissolves.)
- LAYER CHEESE STRATEGICALLY: Sprinkle half the cheddar on top of the soup mixture first, then the mozzarella, then the rest of the cheddar. The mozzarella melts faster and creates a gooey blanket, while the cheddar adds sharpness without sinking to the bottom. (Your future self will thank you for not just dumping it all at once.)
- BAKE UNTIL BUBBLY: Don’t pull it out when it looks golden—wait until the edges are bubbling and the cheese has pulled away from the sides. I used to take it out too soon, and the top would stay dry. A broiler for 1-2 minutes at the end gives that perfect crispy finish, but only if the cheese is fully melted first.
Wine and beer pairings for this dish
Creamy White Wine
This casserole practically begs for a crisp, dry white wine with enough body to stand up to the rich cheese sauce. I reach for a Chardonnay from California—something with bright citrus notes and a touch of vanilla from oak aging.
The La Crema Sonoma Coast Chardonnay is my go-to because it balances the creamy texture without being too heavy. Serve it slightly chilled (45-50°F) to let its acidity cut through the richness. 🍷
Light Lager Balance
For beer lovers, a crisp American lager like Bud Light Platinum or Coors Banquet works beautifully. The light malt sweetness and subtle hop bitterness complement the string beans and sharp cheddar without overpowering them.
I like to chill the beer to 40°F and serve it in a frosty mug to enhance the refreshing contrast. The carbonation also helps cleanse your palate between bites of creamy casserole.
Sparkling Wine Twist
If you're feeling fancy, a demi-sec sparkling wine like Moët Impérial adds a luxurious touch. The bubbles and slight sweetness elevate the dish, making it feel more special for holidays or dinner parties.
I pour mine into champagne flutes and let the effervescence complement the breadcrumb topping's crispy texture. The acidity in the sparkling wine also helps balance the richness of the cheese sauce.
Red Wine Option
For those who prefer red, a light-bodied Pinot Noir from Oregon—like Domaine Serene Willamette Valley Pinot Noir—pairs surprisingly well. Its bright red fruit notes and silky tannins don’t clash with the creamy filling.
Serve it at 60-65°F to let its delicate flavors shine alongside the string beans and garlic. This is a great choice if you're serving the casserole with a side of roasted meats.
Non-Alcoholic Pairings
Don’t have alcohol? No problem! A sparkling apple cider like Martinelli’s Sparkling adds a festive touch with its crisp acidity and subtle sweetness. For something more savory, try a ginger beer like Feather Ginger Beer—the spicy kick complements the cheesy richness without competing.
Both options keep the meal refreshing and crowd-friendly. 🍏
Nutrition facts
Frequently asked questions
Can I use frozen string beans instead of fresh?
Frozen string beans work perfectly and save time. Just thaw them first by soaking in cold water for 10 minutes or microwaving for 2 minutes. Drain well before mixing with the sauce to avoid excess moisture. The texture will be just as tender when baked.
What's the best way to make this casserole extra creamy?
For maximum creaminess, use whole milk instead of skim and add 2 tablespoons of sour cream or half-and-half to the sauce mixture. Also, shred the cheddar cheese yourself for a smoother texture—pre-shredded often contains anti-caking agents that prevent proper melting.
Can I make this ahead of time or freeze it?
Yes! Assemble the casserole up to 24 hours ahead and refrigerate uncovered. Bake straight from the fridge, adding 10-15 extra minutes to the cooking time. For freezing, bake as directed, let cool completely, then wrap tightly in foil. It keeps for 3 months—reheat covered at 350°F for 30-40 minutes.
Why did my casserole get watery?
Watery results usually mean overcooking or too much moisture. Check if you used fresh beans without blanching or added extra milk. For future batches, bake at 350°F for 45 minutes max, and tent with foil if browning too fast. Also ensure your baking dish is properly greased so the casserole doesn't stick and release excess liquid.
What are good side dishes to serve with this?
This rich casserole pairs perfectly with crusty bread for soaking up the sauce, or buttery mashed potatoes for a heartier meal. For a lighter option, try a fresh green salad with lemon vinaigrette or steamed broccoli with garlic butter. The acidity helps cut through the richness and balances the flavors.