Creamy Green Bean Casserole

This easy green bean casserole is loaded with fresh green beans and mushrooms, all coated in a creamy homemade sauce and topped with crispy baked onion rings. It’s a Thanksgiving favorite you can prep a day ahead, giving you a little less to do on the big day!

I’m all about the sides on Thanksgiving, and this casserole has earned its spot next to the turkey. The green beans get a quick blanch before they’re folded into a creamy mushroom sauce, with crispy baked onions mixed into the filling and piled on top.

Ever since I started making it this way, it’s been requested at nearly EVERY holiday. Apparently, one appearance in November just isn’t enough!

You'll Love This Creamy Green Bean Casserole

• That crispy topping! Make your own onions or bake up some frozen onion rings according to the package directions. Either way, the crunch adds such good texture.
• Homemade mushroom sauce, right in the skillet. Mushrooms, onion, and garlic give the creamy filling plenty of savory flavor.
• Get a head start the day before. Prep the filling ahead and keep the onions separate until you’re ready to bake so they keep their crunch.
• Less last-minute juggling. Prepare the beans and sauce while the onions bake, then bring everything together for a quick finish in the oven.

Ingredients You Need

• Green Beans: I recommend fresh green beans over frozen for this recipe. Trim the ends and cut them in half so they’re easier to scoop and eat. A quick blanch gives them a head start before they go into the sauce.
• Mushrooms: These give the homemade sauce its rich, savory flavor. Halve smaller mushrooms and quarter larger ones to keep the pieces roughly the same size.
• Onion: Adds savory flavor and a little natural sweetness to the creamy sauce.
• Chicken Broth: Adds savory flavor to the homemade sauce. Vegetable broth works too if you want to keep the casserole vegetarian.
• Heavy Cream: Gives the sauce its thick, creamy texture. Half-and-half is the only substitute I recommend, since thinner milks won’t give you the same richness.
• Flour: Helps thicken the sauce so it’s creamy and coats the green beans in every bite.
• Garlic: Adds flavor.
• Butter: Adds richness and flavor to the sauce. I prefer it over olive oil for this recipe.
• Onion Rings: Make your own or grab a bag of frozen onion rings for an easy shortcut. I prefer Alexia because they bake up nice and crispy.
• Salt & Pepper: Bring all the flavors together. You’ll use some of the salt in the water for blanching the green beans and the rest in the sauce.

How To Make Green Bean Casserole

Let me walk you through how it comes together. Start by baking the onion rings as directed, then work on the beans and sauce while they’re in the oven.

Blanch the green beans in generously salted water, then transfer them to ice water to stop the cooking. Drain well so you don’t add extra water to the sauce.

Cook the mushrooms, onion, and garlic in butter until softened. Stir in the flour, then gradually whisk in the broth and heavy cream. Cook, stirring, until the sauce is smooth and thickened.

Gently fold the drained beans and about a quarter of the baked onion rings into the sauce, breaking those rings into smaller pieces so they’re easier to mix in. Pile the remaining onion rings on top and bake until hot and bubbly. Then grab your serving spoon!