Green Bean Casserole

This green bean casserole recipe is my favourite.  A classic side of fresh greens beans that are blanched and covered in a creamy homemade sauce and topped with a layer of crispy homey baked onions. This is fresh green bean casserole is totally from scratch. There are no cans of cream of mushroom soup or canned green beans here. The easy, from-scratch sauce tastes lighter and silkier than the sometimes gloopy green bean casseroles made with cans of cream of mushroom soup. The creamy sauce is seasoned deliciously (no bland sauce here) and the mushrooms give it a hearty depth of flavour. The signature crispy onions are also homemade (if you want them to be) and easy to make - I had to stop myself from eating them all before they hit the beans! There is something so comforting about the classics like this savory, creamy & crunchy green bean casserole! I partnered up with Bob’s Red Mill using their Gluten Free 1-1 all purpose flour  to make this classic side dish totally gluten free and delicious!

Green Bean Casserole

Green Bean Casserole Ingredients

  • Green Beans: Fresh green beans are the key. I don’t recommend canned or frozen  green beans for this recipe.
  • Butter: unsalted to sauté the mushroom and onions in
  • Onions: I use a red onion for the crispy baked onions and a yellow one for the sauce itself - but either works for either part
  • Mushrooms:  white or cremini is what I use but really you could use any mushrooms you like. Feel free to leave out the mushrooms or replace with thinly sliced bell pepper if you are not a fan.
  • Seasonings: Salt, pepper, garlic, and a little nutmeg and some dried herbs I like to add but those are optional or you could use your favourite blend of dried herbs in their place. The mustard and W sauce are also optional but they do give a little extra flavour to the sauce.
  • Flour: plain all purpose flour is great here to make the crispy onions and the sauce but I made them gluten free by simply using Bob’s Red Mill Gluten Free 1-1 all purpose flour in its place. I love it and it’s my staple go to for converting simple baked goods into gluten free ones. This gluten free all-purpose flour blend/mix is perfectly formulated to create baked goods with terrific taste and texture—no additional specialty ingredients or custom recipes required, making it one of the best flours for gluten free baking or cooking. Bob’s has a whole variety of products for all sorts of dietary needs
  • Chicken broth: Adds the liquid needed to make the sauce. You could use beef or vegetable broth as well. Water will work in a pinch. You could even replace ¼ cup of it with white wine to help deglaze pan and add even more flavour.
  • Heavy Cream: This adds the creamy rich element to the mushroom sauce that we all know and love. I don’t recommend using only milk or just broth.  Heavy cream makes this sauce extra rich but for a bit of a lighter version use half and half instead.
  • Crispy baked onions: I love this baked recipe for crispy onions below. It’s pretty easy to make and they are delicious- but feel free to use store-bought fried onions to save time.
  • Extra add in: grated cheese in the sauce for a cheesier version, add crispy bacon to the suave or to the topping or switch up the Seasoning and Herb blend in the sauce for a slightly different take.

Green Bean Casserole

Green Bean Casserole

How to make this Creamy Green Bean Casserole:

  1. Start by making the crispy baked onions (if making homemade version - skip if using store bought) - toss onions with the egg and olive oil and spread on baking sheet - sprinkle over flour and toss then bake until golden and crisp - tossing them halfway through
  2. Trim, cut and briefly boil or blanch the green beans. Strain them and transfer the beans immediately into a large bowl of ice water, and give them a quick stir in order to halt their cooking. Once cool statin and set aside.
  3. Prepare your mushroom sauce. Sauté  the mushrooms and onions, garlic and seasonings until golden and cooked. Make roux: Stir in the flour and sauté it for a minute, to cook off that flour-y taste and form the base of our roux. Then stir in some stock, and cream. Bring sauce to a simmer until it has thickened, then taste and season with salt and pepper.
  4. Assemble: Combine the green beans and mushroom sauce. Transfer the mixture to baking dish (or keep in skillet) Sprinkle the crispy onion topping evenly over the top the BAKE

Green Bean Casserole

Green Bean Casserole

Tips for making a great Green Bean Casserole:

  • Draining your green beans well and even patting them out on towels will help ensure they don’t “liquefy” the sauce too much. Make sure the sauce has simmered long enough and  is also quite thick before stirring them in.
  • Don’t feel like making your own crispy onions - no problem - just use store bought - approx 1 ½ cups fried onions (about 4 ½ ounces)
  • Instead of fried onions, you can also top the casserole with 1 cup of panko breadcrumbs that have been mixed with 2 tablespoons melted butter to get a crispy topping.
  • Chop your beans in half or in thirds for easier eating or leave them whole. Either approach works.

Green Bean Casserole

I have partnered up with Bob’s Red Mill to bring you this fabulous recipe, but all opinions are my own. Thank you for supporting Olive & Mango.

Green Bean Casserole

More Turkey Dinner Sides You’ll Love:


Servings: 6
Prep Time: 20 mins
Cook Time: 1 hr 15 min (40 min without the homemade baked onions)


For the oven baked crispy onions (optional)

For beans and sauce

  • 1 pound fresh green beans, rinsed, and ends trimmed
  • 2 tablespoons unsalted butter
  • 12 ounces mushrooms, trimmed and cut into ½-inch pieces
  • ½ teaspoon freshly ground black pepper
  • 2 cloves garlic, minced
  • ¼ teaspoon freshly ground nutmeg
  • 1 teaspoon dried thyme
  • 1 teaspoon dried parsley
  • ¼ teaspoon dried oregano
  • ¼ cup tablespoons all-purpose flour
  • 1 cup chicken broth
  • 1 cup half-and-half or heavy cream
  • 1 teaspoon dijon Mustard (optional)
  • 1 teaspoon Worcestershire sauce (optional)


For the baked crispy onions

  1. Preheat the oven to 400°F.
  2. Cut the onion in half and then slice each half as finely as you can, making sure the slices are not attached to each other.
  3. Whisk the egg in one large bowl, add the oil and combine, then add the onions to the bowl and toss to fully coat.
  4. Spread onions evenly on a large greased or lined baking dish so that they don’t overlap too much
  5. Add one tablespoon of the flour to a sieve and sift it all over the onions. Mix them around the sheet with two forks, and repeat with the second tablespoon of flour. Mix and toss again with the forks and spread the onions on the baking sheet.
  6. Bake for about 20 minutes, stir again with tongues or forks, and bake for 15 more minutes or until they are crispy. Take out and let them cool on the baking sheet.

For the beans:

  1. Bring a large pot of salted water to boil and boil greens for 5 minutes (for standard green beans) or 2 to 3 minutes (for haricot vert, or skinny ones).
  2. Drain beans, then plunge them into ice water to full stop them from cooking. Drain again, and set aside

For the creamy mushroom sauce:

  1. Melt the butter in a 12-inch cast iron skillet set over medium-high heat. Add the  onions and sauté unit softened and just starting to get golden on the edges 4-5 min
  2. Add mushrooms, 1 teaspoon salt and pepper and cook, stirring occasionally, until the mushrooms begin to give up some of their liquid, approximately 4 to 5 minutes.
  3. Add the garlic and nutmeg and other dried herbs and continue to cook for another 1 to 2 minutes.
  4. Sprinkle the flour over the mixture and stir to combine. Cook for 1 minute. Add the broth and simmer for 1 minute. Decrease the heat to medium-low and add the half-and-half. Cook until the mixture thickens, stirring occasionally, approximately 8-10 minutes.
  5. Assemble and bake: Add cooked greens beans to sauce and stir until they are coated. Transfer to casserole dish (or leave as is if baking in the skillet ) Sprinkle crispy onions over the top. Bake at 400 degrees F  for 15 minutes, or until sauce is bubbling and onions are a shade darker. Serve
  6. Leftovers can be stored refrigerated in a sealed container for up to 3 days. (the alfredo sauce does not freeze well, so I do not recommend freezing this casserole.)

Recipe Notes

  • Make in a skillet: You don’t have to transfer the beans to a casserole dish like I did - (I used a buttered 8x11 dish) you can bake this green bean casserole right in the large cast iron skillet
  • Don’t feel like making your own crispy onions - no problem - just use store bought - approx 1 ½ cups fried onions (about 4 ½ ounces)

Make Ahead

  • Onion Topping - You can store leftovers room temperature, loosely wrapped (they’d get soggy in an airtight container) But you can pop them in the oven again and they’ll get crispy. If you’re not really into the baked “fried” onions, leave it out completely and sprinkle the top of the casserole (before going into the oven) with ½ cup Panko breadcrumbs for crunch.
  • Green beans can be blanched and kept in fridge until needed, at least two days. Green beans with mushroom sauce can be made ahead and tossed together and kept covered and refrigerated for up to a day. Right before baking, too casserole with crispy onions and bake per instructions.
  • For extra thick sauce: use 1 extra tablespoon butter and 1 extra tablespoon flour in the sauce — i.e. more roux makes thicker sauces.

Green Bean Casserole