This keto green bean casserole has everything you love about the classic: tender whole green beans in a creamy mushroom sauce, baked until bubbly. There’s no canned soup and no flour. The sauce gets its body from browned mushrooms, cream cheese, heavy cream and a good melty cheese instead.

How to make keto green bean casserole without canned soup

Canned cream of mushroom soup is thickened with flour. Here, the flavor comes from browning the mushrooms well, until their liquid cooks off and they turn golden. Then cream cheese, heavy cream and cheese give the sauce its body. I used smoked gouda because it was a better price, but any cheese that melts well works.

Can you use frozen green beans?

Yes. I used fresh green beans and left them whole, but frozen work too. If you use frozen green beans, thaw them and pat them very dry first. Frozen beans release a lot of water as they bake, which can thin out the sauce.

About the fried onions

I topped mine with the classic fried onions, because I love them. Just know what you’re choosing: they’re coated in wheat flour, so they aren’t gluten-free, and they’re where most of the carbs in a traditional green bean casserole come from. A sprinkle on top before it goes in the oven (covered, so they don’t burn) is a great place to spend a few carbs if they matter to you. That’s what using carbs strategically looks like. If you’re avoiding gluten or keeping carbs very low, leave them off. The casserole is still creamy, savory and satisfying without them.

Keto Green Bean Casserole with Mushrooms

A creamy keto, low-carb green bean casserole with whole green beans, browned mushrooms and melty cheese. No canned soup or flour. Naturally gluten-free without the optional fried onions.

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Prep Time 20 minutes mins

Cook Time 40 minutes mins

Total Time 1 hour hr

Course Side Dish

Cuisine American

Servings 8 servings

Ingredients

  

• 1 1/2 lb Fresh green beans trimmed and left whole (or cut into 2-inch pieces if you prefer)
• 2 tbsp Butter
• 1/2 Medium onion finely diced
• 8 oz Mushrooms chopped; fresh or canned and well-drained
• 2 Garlic cloves minced
• 1/4 cup Chicken broth check the label if you need it gluten-free
• 4 oz Cream cheese softened
• 3/4 cup Heavy cream
• 1/2 cup Smoked gouda shredded, or any cheese that melts well
• Salt and pepper to taste
• Fried onions optional topping; contain gluten

Instructions

 

• Preheat: Heat the oven to 375°F.
• Blanch the beans: Boil the whole green beans for 3 to 4 minutes, then transfer them straight to ice water. Drain and pat dry.
  
• Cook the onion: Melt the butter in a large skillet over medium-high heat. Cook the onion until soft.
  
• Brown the mushrooms: Add the mushrooms and cook until their liquid cooks off and they turn golden, 8 to 10 minutes.
  
• Add the garlic: Stir in the garlic and cook until fragrant, about 30 seconds. Deglaze the pan with the broth.
  
• Blend the cream: Blend the softened cream cheese, broth, and heavy cream until smooth. A blender or food processor keeps the sauce from getting lumpy.
  
• Make it creamy: Pour the cream mixture into the skillet and stir in the cheese until melted. Simmer 3 to 5 minutes, until thickened. Season with salt and pepper.
  
• Assemble: Toss the beans in the sauce and spread them in a baking dish. If using fried onions, sprinkle them on top.
  
• Bake: Cover with foil and bake for 20 to 25 minutes, until bubbly. Covering keeps the fried onions from burning.
  

Notes

Fried onions: Store-bought fried onions contain wheat flour, so they aren’t gluten-free, and they add most of the carbs in a classic green bean casserole. Leave them off, or add them if you love them and gluten isn’t a concern.

Cheese: Use any cheese that melts well. I used smoked gouda because it was a better price, and it adds a nice smoky flavor. Parmesan, Gruyère or white cheddar all work too.

Make ahead: Make the sauce and blanch the beans the day before. Assemble, cover, and refrigerate, then bake on the day.

Keyword green bean casserole without canned soup, keto green bean casserole, low carb green bean casserole, low carb thanksgiving side

Make it ahead

Make the sauce and blanch the beans the day before, toss them together, spread in the baking dish, cover, and refrigerate, then bake the day of. If you’re using fried onions, add them right before it goes in the oven.

Got a green bean hater at the table?

Mix some of the sauce with peas instead. I made a little dish of creamy mushroom peas for someone who doesn’t like green beans, and he said it was good! Peas are higher in carbs than green beans, so keep that in mind if you’re counting.

Diet notes

Without the fried onions, this casserole is naturally gluten-free, as long as your broth is (check the label). It fits a keto or low-carb way of eating, and I always list total carbs so you can make the call that fits how you eat.

Planning a holiday menu? See all my low-carb Thanksgiving sides, including mashed delicata squash and cauliflower cheese.

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