We’ve taken a holiday favorite and given it a fresh face with our Low Carb Fresh Green Bean Casserole. We’re guessing the traditional casserole (canned green beans, cream of mushroom soup, milk, a little pepper, and a topping of crispy fried onions) has been on your table for what seems like forever – it just doesn’t feel like the holidays without it, right? What if we told you that you can still deliver a green bean casserole but with ramped up flavors and textures, with only 10 minutes extra prep time? In our humble opinion, it’s definitely worth the effort!
Let’s talk about the improvements (or so we like to think). We start with fresh green beans, because they’re hard to beat. But frozen or canned green beans work just fine in this recipe. We substitute low carb Alfredo sauce (our favorite is Rao’s) for the pedestrian cream of mushroom soup, and throw in some diced water chestnuts (optional of course), fresh mushrooms caramelized in butter and minced shallot, Parmesan cheese, and toasted pecans. We’ve reduced total net carbs in this casserole by over 50 when using water chestnuts and pecans in place of the fried onions!
Preheat the oven to 375 degrees F. Trim the ends of the green beans with a sharp knife and place in a large microwaveable bowl with a little water on the bottom. Cover with vented top and heat on high, according to your desired level of doneness. We like ours crisp-tender, so we microwaved for 5 minutes. If you prefer a more tender bean like you’d find in canned, continue microwaving. You can substitute with 32 ounces of frozen green beans (heat according to directions), or 4 cans of drained green beans; no preheating necessary. Place the beans in a buttered, 9 x 13 casserole dish.
Heat oil over medium heat in a heavy, deep skillet. Add butter and heat until it starts to foam, then increase the heat to high and add sliced mushrooms. Let them cook, undisturbed for about 3-4 minutes or until the bottoms are beautifully caramalized. Flip, and cook another 3 minutes. Next, stir in the minced shallots, but for only a minute or two. You want them to be soft, not browned.
Add in the Alfredo sauce, the water chestenuts (optional) Parmesan cheese, cracked pepper, and stir. Then pour the mixture over the beans and stir. Bake about 25 minutes, or until bubbly. Top with 1/2 cup chopped pecans that have been toasted in a small skillet. Serve immediately.
We hope you enjoy our take on the traditional green bean recipe as much as we do, and from our family to yours, bon appetite!
Low Carb Fresh Green Bean Casserole

Our Low Carb, Fresh Green Bean Casserole is a twist on a classic holiday side dish. Low carb Alfredo sauce, sliced water chestnuts, fresh mushrooms, shallots, Parmesan cheese, and toasted pecans, bring new flavors and textures to a family favorite, with only 6 net carbs per keto-friendly serving!
- 9x13 casserole dish
- 2 lbs fresh green beans
- 2 tbsp olive oil
- 2 tbsp butter (divided)
- 1 medium shallot (minced)
- 8 oz fresh mushrooms (sliced)
- 15 oz Alfredo sauce (low carb jarred (we use Rao's))
- 5 oz water chestnuts (8 oz canned, drained (optional))
- 4 oz Parmesan cheese (shredded (1 cup))
- ½ tsp freshly ground pepper
- ½ cup pecans (chopped (optional))
Preheat oven to 375°F. Wash and trim green beans. Place in large microwave-safe bowl. Add 4T water to cover bottom of bowl. Cover with plate or vented microwavable cover. Microwave for 5 minutes for crisp-tender. Increase time to desired level of doneness. Drain and place in buttered 9x13 baking dish. Substitute 32oz frozen green beans and heat according to directions, or use 4 cans drained green beans, no preheating necessary.
In a heavy, deep skillet, heat oil over medium heat. Add butter until foamy. Increase heat to high, add mushrooms and cook, undisturbed, for 3-4 minutes until they've caramelized on the bottom. Flip mushrooms over and cook another 3 minutes, or until mushrooms are browned. Stir in shallots and continue cooking 1 minute.
Add Alfredo sauce, water chestnuts, Parmesan cheese, and pepper. Pour over green beans and mix. Bake until bubbly, about 30 minutes. Toast pecans in 1T butter in small skillet over medium heat 1-2 minutes. Sprinkle over casserole before serving.
Store leftovers covered in refrigerator for up to 5 days. Reheat in 375 degree oven until hot. One serving equals 3/4ths cup.