Green Bean Casserole Classic (Print view)

A baked combination of tender green beans and creamy mushroom sauce topped with crisp onions.

# What You'll Need:

→ Vegetables

01 - 1 pound fresh green beans, trimmed and cut into 2-inch pieces (or 1 pound frozen, thawed)
02 - 1 small yellow onion, finely chopped
03 - 2 cloves garlic, minced
04 - 8 ounces cremini or button mushrooms, sliced

→ Sauce

05 - 2 tablespoons unsalted butter
06 - 2 tablespoons all-purpose flour
07 - 1 cup whole milk
08 - 1/2 cup low-sodium vegetable broth
09 - 1/2 cup sour cream
10 - 1/2 teaspoon salt
11 - 1/4 teaspoon black pepper
12 - 1/4 teaspoon ground nutmeg

→ Topping

13 - 1 1/2 cups crispy fried onions (store-bought or homemade)

# Cooking Steps:

01 - Set oven temperature to 350°F.
02 - Bring a large pot of salted water to a boil. Add green beans and cook for 4 to 5 minutes until bright green and tender. Drain and immediately plunge into ice water to stop cooking. Drain again and set aside.
03 - Melt butter in a large skillet over medium heat. Add chopped onion and cook for 2 to 3 minutes until softened. Add garlic and mushrooms; cook for 5 minutes until mushrooms are tender and liquid has evaporated.
04 - Stir in flour and cook for 1 minute while stirring constantly. Gradually whisk in milk and vegetable broth. Cook, stirring continuously, until the sauce thickens, about 3 to 4 minutes.
05 - Remove skillet from heat. Stir in sour cream, salt, black pepper, and ground nutmeg until smooth.
06 - Add drained green beans to the sauce and gently mix to coat evenly.
07 - Transfer the green bean and sauce mixture to a greased 2-quart baking dish. Sprinkle 1 cup of crispy fried onions evenly over the top.
08 - Bake for 25 minutes until bubbly.
09 - Remove dish from oven. Top with remaining crispy fried onions and bake an additional 5 minutes until golden brown.
10 - Allow the dish to rest for 5 minutes before serving.

# Expert Ideas:

01 -
  • It comes together in under an hour, which means you can focus on other dishes instead of hovering over the stove.
  • The contrast between creamy sauce and crispy onions is genuinely addictive, and it works for any season, not just holidays.
  • Once you make it once, you'll stop buying the canned version and never look back.
02 -
  • Don't skip the ice bath for green beans—it stops them from overcooking and keeps them from turning that sad olive-green color.
  • Add the sour cream only after removing from heat; hot sour cream can break and turn grainy.
  • Save half the fried onions for the very end so they stay crispy instead of absorbing sauce during the full baking time.
03 -
  • Make your mushroom sauce the morning of and refrigerate it separately—this saves time and lets flavors deepen before baking.
  • Use freshly ground nutmeg if you can find it; the difference in flavor is worth the tiny extra effort.
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