Weight Watchers Tuna Casserole

This Low-Carb Tuna Casserole is inspired by the classic tuna bake. Instead of using pasta, I use finely shredded cabbage, sautéed with onions until it gets that slight toasty edge. Mushroom soup mix gives this veggie-packed baked casserole a creamy base. 

The result is glo-ri-ous! And all for 1 WW Point. You may never go back to the traditional tuna casserole with pasta. If you’re looking for more fall and winter casserole ideas, head over to our Weight Watchers Casseroles page!

Why should you try low-carb Tuna Casserole?

There are plenty of reasons to give this Low Carb Tuna Casserole a go, and here are a few that stand out:

1. Quick and Convenient: We’ve all had those days when the chicken or beef in the freezer feels like a solid rock, and the thought of waiting for it to thaw is just too much. Sure, the microwave can help, but it’s never quite the same, right? That’s where a recipe like this one shines. With a couple of cans of tuna, you can have a creamy, filling meal on the table in no time. This casserole is warm, comforting, and so low in points that you won’t believe how little effort it takes.
2. Budget-Friendly: Not only is this meal low in points, but it’s also one of the most affordable recipes on the blog. If you’re watching your wallet or need to feed a crowd without breaking the bank, this Low Carb Tuna Casserole is your go-to. Whip up a couple of trays, and you’ll have everyone satisfied. It’s the perfect dish to keep in your back pocket for those days when you’re low on budget or time.
3. Low in Carbs, High in Satisfaction: By swapping out the traditional pasta for shredded cabbage, you’re not only cutting down on carbs but also adding a delicious texture that complements the creamy tuna mixture perfectly. The cabbage gets a slight crisp when baked, providing a nice contrast to the soft, creamy filling.

Preparation Time: 15 minutes

Cooking Time: 25 minutes

Servings: 4 servings

Serving Size: 1 casserole portion (430 g.)

1 WW Point Per Serving. You can view the recipe on the WW App here. (WW login required.)

Ingredients:

• 1 teaspoon olive oil (5 ml)
• 2 cloves garlic, minced
• 1 medium onion, diced (about 1 cup, 150 g)
• 4 cups finely shredded white cabbage (300 g)
• 1 red bell pepper, diced (about 1 cup, 150 g)
• 1 packet of cream of mushroom soup mix
• ½ cup water (120 ml)
• ½ cup skim milk (120 ml)
• 1 cup corn kernels, drained (150 g)
• 1 can tuna in water, drained (10 oz / 285 g total)
• 1 teaspoon dried thyme (or fresh, if available)
• Salt and pepper to taste

Instructions:

1. Prep the Vegetables: Finely shred the cabbage, ensuring that the pieces are all about the same size to ensure even cooking. Dice the onion and red bell pepper, and set them aside. Mince the garlic.
2. Sauté the Aromatics: Heat 1 teaspoon of olive oil in a large pan over medium heat. Once hot, add the minced garlic and diced onion. Sauté for about 2–3 minutes, stirring frequently, until the onion becomes soft and translucent.
3. Cook the Cabbage and Bell Pepper: Add the shredded cabbage and diced red bell pepper to the pan. Stir everything together, cooking for another 5–7 minutes. You want the cabbage to soften and begin to brown slightly, which adds a nice toasted flavor to the casserole. Stir occasionally to avoid burning, but allow the cabbage to cook long enough to develop a little bit of color.
4. Prepare the Soup Base: In a small bowl, mix the packet of cream of mushroom soup with ½ cup of water and ½ cup of skim milk. Stir until the soup mix is fully dissolved. This will serve as the creamy base of your casserole.
5. Assemble the Casserole: Preheat your oven to 350°F (175°C). In a large mixing bowl, combine the sautéed cabbage, bell pepper, corn kernels, and drained tuna. Pour the prepared soup mixture over the vegetables and tuna. Add 1 teaspoon of dried thyme and season with salt and pepper to taste. Stir everything until well combined, ensuring the creamy soup mixture coats all the ingredients evenly.
6. Transfer to a Baking Dish: Grease a medium-sized baking dish lightly with a small amount of oil or cooking spray. Transfer the casserole mixture into the dish, spreading it out evenly.
7. Bake the Casserole: Bake in the preheated oven for 20–25 minutes, or until the casserole is heated through and the top is slightly golden and bubbly. If you prefer a crispier top, you can turn on the broiler for the last 3–5 minutes of cooking, but be sure to keep an eye on it to avoid burning.
8. Serve: Remove the casserole from the oven and let it cool for a few minutes before serving. If desired, you can sprinkle a bit of fresh thyme or a squeeze of lemon juice over the top for a fresh finish. Serve hot and enjoy!

Variations and Substitutions

Here are a few variations and substitutions you can try with this Low Carb Tuna Casserole:

1. Traditional Pasta Option: If you’re not strictly watching your carbs, you can always opt to use pasta or even a combination of pasta and cabbage. Just keep in mind that this will increase the points value of the dish. Whole wheat pasta could be a good compromise if you’re looking for a slightly healthier option.
2. Added Veggies: While peas are a traditional choice, I often prefer using sweet yellow corn kernels. They add vibrant color and a subtle sweetness that pairs beautifully with the savory flavors in the dish. For a healthier twist, I also recommend trying green beans—they bring a lovely crunch and balance the heartiness of the casserole.
3. Cheese, Please: Casseroles and cheese are a match made in heaven. A little bit of mozzarella or even a sprinkle of Parmesan on top before baking can add a delightful, gooey layer that makes this dish even more comforting.

Tips and Tricks for Making Low-Carb Tuna Casserole

Here are a few tips to ensure your Low Carb Tuna Casserole turns out perfectly every time:

1. Finely Shred the Cabbage: Make sure your cabbage is finely shredded and uniform in size. This ensures that it cooks evenly and mixes well with the other ingredients. If you’re short on time, a bag of pre-shredded coleslaw mix works just as well.
2. Use Tuna in Water, Not Oil: Always opt for tuna packed in water rather than oil. The oil can add unnecessary points, and it’s difficult to drain all of it, which can make the casserole greasier than intended. Tuna in water keeps things light and helps maintain the right texture.
3. Season Generously: Don’t be afraid to season your casserole well. The tuna, cabbage, and mushroom soup mix all have subtle flavors, so a good pinch of salt, pepper, and perhaps some dried herbs like thyme or oregano can really elevate the dish.
4. Add a Squeeze of Lemon: Just before serving, a squeeze of fresh lemon juice can brighten up the flavors and add a nice tangy contrast to the creamy, savory casserole.