Green Bean Casserole from Scratch

Side DishThanksgivingComfort FoodVegetarian

Classic green bean casserole with fried onion topping, from scratch! Easy to make ahead. So much better than canned!

Photography Credit: Megan Keno

A Thanksgiving Must-Have

Our family, like every other family at Thanksgiving, is no stranger to green bean casserole, with its crunchy fried onion topping and rich, creamy filling. Truth be told, it’s one of my favorites, along with the jellied cranberry sauce.

But over the years, I have come to expect more from my green bean casserole than just opening up a few cans of beans, soup, and sprinkling on some prepared fried onions.

Here is my totally from-scratch version – you’ll never look at green bean casserole the same way again.

Classic Green Bean Casserole made from scratch

Homemade Fried Onion Topping — Better than French’s!

Frying your own onions gives them a crunchy texture that can’t be beat by anything from a can. The onions are soaked in buttermilk and then coated with crispy Panko crumbs, herbs, and flour before being fried to a golden crisp.

This said, if you’d like to give yourself a short-cut on this most-busiest of holidays, French’s Fried Onions make a fine substitute. Trader Joe’s also makes a brand that we really like!

Homemade Mushroom Cream Sauce — Better than the can!

I also make my own mushroom cream sauce. Button and Crimini mushrooms are always a good choice here, but try buttery Chantrelles if you want something a little more decadent. Mixing up the mushrooms is one way to give this dish a different flavor and make it stand out.

We don’t suggest swapping this cream sauce for canned cream sauce. The casserole just isn’t as good!

Classic Green Bean Casserole Classic Green Bean Casserole

A Make-Ahead Thanksgiving Dish

This dish can be made ahead of time and kept in the fridge until ready to heat. To keep the fried onions crispy, store them separately in an airtight container on the counter. Wait to top the casserole until just before baking .

It’s hard to go back to the canned version after this!

Looking for more Thanksgiving Sides from Scratch? Here you go!

Video: How to Make Green Bean Casserole

Updated November 15, 2018 : We spiffed up this post a little to make it sparkle! No changes to the recipe.

Green Bean Casserole from Scratch Recipe

  • Prep time: 45 minutes
  • Cook time: 20 minutes
  • Yield: 8 to 10 servings

Make-ahead: Store the fried onions in an airtight container at room temperature and refrigerate the prepared filling. Wait to top the casserole with the onions until just before baking. Cooking time may be slightly longer.


For the fried onions:

  • 1 red onion, thinly sliced
  • 1 1/2 cup buttermilk
  • 1 cup all-purpose flour
  • 1 cup Panko crumbs
  • 2 tablespoon mixed dried herbs - parsley, dill, thyme, whatever you want!
  • Salt, for seasoning
  • Vegetable oil, for frying

For the casserole:

  • 2 pounds green beans, trimmed and cut into 2-inch lengths
  • 1/4 cup (1/2 stick) regular salted butter
  • 1 pound crimini or button mushrooms, trimmed and sliced
  • 3 cloves garlic, minced
  • 2 teaspoons fresh thyme (or 1 teaspoon dried thyme)
  • 2 to 3 tablespoons all-purpose flour
  • 1 1/4 cup half-and-half
  • 1 1/4 cup low sodium chicken broth
  • 1/2 cup grated Parmesan cheese


1 Prepare the onions for frying: In a bowl, combine the sliced red onions and the buttermilk. Toss to coat the onions, then place them in the fridge for at least 15 minutes.

In another small bowl, whisk together flour, panko, and dried mixed herbs.

Classic Green Bean Casserole Classic Green Bean Casserole

2 Heat the oil for deep-frying: Fill a Dutch oven or other deep pot with about 2 inches of vegetable oil, and heat to 375F, or until shimmering but not smoking (lower the heat if you start to see wisps of smoke). To check that the oil is hot enough, toss in a pinch of panko mixture; if it starts to bubble and fry, you’re ready to go.

Set a baking sheet lined with paper towels near the stove to drain the fried onions.

3 Deep-fry the onions: Working in handfuls, lift the onions from the buttermilk and toss them in the flour/panko mixture.

Gently lower the coated onions into the hot oil and fry until deep golden brown. Lift the onions from the oil with a heat-proof slotted spoon or tongs, and place on the paper towels to drain.

Classic Green Bean Casserole

4 Preheat the oven to 375F. Set a strainer over your sink and prepare a bowl with ice water.

5 Blanch the green beans: Bring a large pot of salted water to a boil. Add the green beans and boil for 5 to 6 minutes until just tender, but still slightly crisp.

Drain and then shock the green beans in the bowl of cold water to stop the cooking process. When cool, drain again and set aside.

Classic Green Bean Casserole Classic Green Bean Casserole

6 Cook the mushrooms: Melt the butter in a large skillet and add in the mushrooms. Season with salt and cook until softened and tender. Add in the garlic and thyme.

7 Make the creamy sauce: Sprinkle the flour over the mushrooms and stir until the mushrooms are coated. Stir in the half-and-half and the chicken broth.

Bring the mixture to a simmer and allow the sauce to thicken. Stir in the Parmesan cheese and green beans.

Classic Green Bean Casserole

8 Assemble and bake the casserole: Transfer the creamy green bean and mushroom mixture to a 3-quart or 9x13 casserole dish. Scatter the fried onions over top, and bake in the oven for 15 to 20 minutes, until the casserole is bubbling. Serve hot.

Classic Green Bean Casserole Classic Green Bean Casserole

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Megan Keno

Megan Keno, is the writer, recipe developer, and photographer behind the nationally recognized food blog Country Cleaver. Her work has been featured in Country Living Magazine, Better Homes and Gardens, America’s Test Kitchen, The Kitchn, and on The Pioneer Woman’s Tasty Kitchen Blog.

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28 Comments / Reviews

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Did you make it? Rate it!

  • Susan

    Love your site! How far in advance can I assemble and refrigerate the casserole (minus the onions, of course)? Can I do it the day before? Thanks.

  • Henry

    I do one like this from scratch, but add some sherry and teaspoon or so of Worcestershire sauce. Really adds some depth to the mushroom cream sauce!

    I’ve also been know to stretch the mushroom cream sauce out a bit more into a cream of mushroom soup

  • Tara

    I just made this tonight for me and my toddler. It looks amazing! I used the french’s fried onions as I actually didn’t realize the recipe called for fried onions from scratch (I just watched the video quickly on the side of the banana bread recipe I made last night which is the best bread ever and I make it all the time!! the casserole looked so yummy and easy, i thought I’d give it a try it for tonight!) It was really fast to make, less than 30 mins and makes for a good side dish to my simple shake and bake chicken. Thanks for another fabulous recipe! :)

  • Kelly K

    There’s no better green bean casserole recipe. If you’re not making it from scratch… don’t bother.


  • Heather

    I’m making a gluten free version of this for our Christmas dinner tonight, and will report back. I can tell you that the mushroom sauce smells and tastes absolutely heavenly! I substituted corn starch for the flour, and because I’ve been sick with a horrible cold for weeks, I bought gluten free French fried onions at Sprouts rather than making them myself.

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