This low carb keto tuna casserole is a makeover version of the classic casserole, but with a few healthy and low carb twists. We’re swapping out the noodles for squash noodles, canned soup for a delicious homemade sauce, and a crunchy topping that doesn’t require crackers! It may be a healthy tuna casserole, but it’s so delicious that no one will mind — and I’ll bet you’ll enjoy this one even if you aren’t keto.
What Is Tuna Casserole?
Tuna casserole is an old classic casserole made up of cream of mushroom soup, noodles, tuna, and perhaps a few vegetables. I’ve upgraded the original to add vegetable noodles and made a homemade sauce that is much more flavorful than anything you’ll find in a can.
Is Tuna Casserole Healthy?
Tuna casserole is not necessarily known as a health food. But this recipe is changing all of that! By swapping out the noodles for vegetable noodles, a homemade sauce made without thickeners, and making a crunchy topping without the crackers, we’ve given this a healthy makeover.
Ingredients You’ll Need
This section explains how to choose the best ingredients for keto tuna noodle casserole, what each one does in the recipe, and substitution options. For measurements, see the recipe card below.
Olive Oil – Or avocado oil. Yellow Squash – Spiralize it to make noodles for the casserole. You have a few options for other “noodles” below.Sea Salt & Black Pepper Onion – I used a white onion, but you could also use a yellow onion if you prefer.Green Bell Pepper – Adds nice crunch and color to the casserole, instead of the traditional green peas. (If you are low carb, depending on your macros, you may be fine with using actual peas here instead.) Also, feel free to saute some mushrooms and add them to the casserole along with the green peppers.Garlic – Use fresh minced garlic for best flavor or jarred for convenience. Chicken Broth – Adds flavor to the sauce. You could also use vegetable broth to make this dish pescatarian, or bone broth for a deeper flavor and nutrition benefits.Heavy Cream – Gives the sauce a creamy texture and flavor. Full-fat coconut milk is fine to substitute if that’s what you have on hand.Parmesan Cheese – Use grated parmesan cheese in both the sauce and the topping. In the sauce, the parmesan acts as a thickener, but you can also thicken with cream cheese, xanthan gum, or other cornstarch substitutes if you prefer. Softer cheeses, such as mozzarella or cheddar cheese, don’t generally work as well for thickening this sauce, but you can stir them directly into the casserole if you like.Tuna – You’ll need 3 5-ounce cans tuna. I prefer solid white albacore tuna for the best texture in a casserole. If you’re not a fan of tuna, feel free to substitute canned salmon instead.Crushed Pork Rinds – These are used for the topping, in place of a crunchy chip or cracker topping that you might find in a traditional tuna casserole recipe. You can make your own pork rinds or buy them. Either way, blitz them in a blender to make the consistency of breadcrumbs.
How To Make Healthy Tuna Casserole
This section shows how to make keto tuna casserole, with step-by-step photos and details about the technique, to help you visualize it. For full instructions, including amounts and temperatures, see the recipe card below. This low carb tuna casserole is made with yellow squash, but you can use all kinds of low carb pasta alternatives! Here is how to use the most common ones:
Zucchini Noodles – You’ll prepare the zucchini noodles the same way you would the squash noodles. They are very similar in taste and texture. Shirataki Noodles – Follow my shirataki noodles method for noodles that have a nice bite and aren’t soggy. After the stir fry step, you can transfer them to the baking dish. Keto Egg Noodles – Prepare keto egg noodles and right after you take them out of the boiling water, transfer them to the baking dish and top with sauce. Cauliflower Rice – After you saute the cauliflower rice, you can add it to the baking dish. Spaghetti Squash – Roast spaghetti squash in the oven, remove the strands with a fork, then add to the casserole dish and top with sauce.
Storage Instructions
Store: Keep leftover keto tuna noodle casserole in the fridge for 3-4 days. (Freezing is not recommended.)Meal prep: Make sauce and prep noodles. Assemble and bake right before serving.Reheat: Reheat in a 350 degree F oven for best results. Microwaving can work, but the noodles will be more mushy.
More Easy Keto Casserole Recipes
If you like this healthy tuna casserole from scratch, you might also like these other keto casserole recipes: You want them to keep the heat high enough to cook away the extra moisture. The end result should be tender, but not super mushy. This reader favorite recipe is included in The Wholesome Yum Easy Keto Carboholics’ Cookbook! Inside this beautiful hard cover keto recipe book, you’ll find 100 delectable, EASY keto recipes to replace all your favorite carbs: bread, pasta, rice, potatoes, desserts, and more… each with 10 ingredients or less! Plus, a photo, macros, & tips for every recipe. ORDER NOW Share your recipe picture by tagging @wholesomeyum and hashtag it #wholesomeyum on Instagram, or in our Facebook support group, too – I’d love to see it! Recipe from the Easy Keto Carboholics’ Cookbook.
