This stovetop tuna casserole is a quick, creamy one-pot dinner made with gluten-free shell pasta, tender broccoli, tuna, coconut milk, and savory broth. It comes together in about 20 minutes with minimal cleanup and plenty of comforting flavor.
When you need a practical weeknight meal without turning on the oven, this is a great option to keep in your back pocket. Everything cooks in the same deep pot, including the pasta, so there is no separate pot of boiling water or baking dish to clean afterward.
The combination of chicken broth and full-fat coconut milk gives the pasta enough liquid to cook while gradually creating a creamy sauce. Nutritional yeast adds a subtle savory, cheese-like note without overpowering the tuna, and small broccoli florets bring color and a tender bite.
The key is simply to stir the pasta regularly as it simmers. Gluten-free noodles can behave differently depending on the ingredients they are made from, so keeping an eye on the texture near the end helps you get a creamy casserole rather than dry or overcooked pasta.
Stovetop Tuna Casserole Ingredients
Gluten-free shell pasta: Small shell-shaped noodles work especially well because their curves catch some of the creamy sauce. Use certified gluten-free pasta when necessary for your dietary needs.
Canned tuna: Drain the tuna thoroughly before adding it so excess packing liquid does not thin the sauce. Gently breaking it into chunks gives you tuna throughout every serving without turning it into a paste.
Broccoli: Chop the florets fairly small so they soften quickly and finish cooking at roughly the same time as the pasta.
White onion: A small amount of diced onion creates a savory foundation for the casserole and develops a gentler flavor after a few minutes of sautéing.
Fresh garlic: Minced garlic adds another layer of savory flavor to the vegetable base.
Full-fat coconut milk: This provides much of the casserole’s creamy texture. Full-fat coconut milk works better here than a thin coconut beverage because the extra richness helps form the sauce.
Chicken broth: The broth provides the main cooking liquid for the pasta while adding savory depth.
Nutritional yeast: One to two tablespoons add a mild cheese-like flavor. Start with the smaller amount and add more after tasting if desired.
Avocado oil: Used for sautéing the onion, garlic, and broccoli before the remaining ingredients go into the pot.
Salt and black pepper: Simple seasoning enhances the vegetables, pasta, and tuna without covering their flavors.
Fresh parsley: Chopped parsley is added at serving time for a fresh finish and a little extra color.
Cooking Steps
STEP 1: Heat the avocado oil in a large, deep pot over medium heat. Add the diced onion and minced garlic and cook for about 3 to 4 minutes. Stir regularly so the garlic does not scorch. The onion should soften and become lightly translucent.
STEP 2: Add the small broccoli florets to the onion mixture. Cook for another 3 to 4 minutes, stirring occasionally, until the broccoli turns bright green and begins to soften. Season with the salt and freshly ground black pepper.
STEP 3: Add the well-drained tuna. Use a wooden spoon to gently separate it into smaller pieces while folding it through the broccoli and aromatics. You want bite-size flakes rather than completely shredded tuna.
STEP 4: Pour in the chicken broth and full-fat coconut milk. Stir everything together, scraping across the bottom of the pot to incorporate any flavorful bits left from sautéing the vegetables. Increase the heat to medium-high and bring the liquid to a gentle boil.
STEP 5: Stir in the gluten-free shell noodles. Once the liquid returns to a simmer, adjust the heat as needed to maintain steady bubbling without an aggressive boil. Cook for approximately 10 to 12 minutes, stirring frequently so the noodles cook evenly and do not stick to the pot.
STEP 6: Watch the casserole closely during the final few minutes. Continue stirring as the pasta absorbs the cooking liquid and the remaining broth and coconut milk become thicker and creamier. If you prefer softer noodles, allow another minute or two of gentle simmering.
STEP 7: Stir in the nutritional yeast, starting with 1 tablespoon. Taste and add the second tablespoon if you want a stronger savory flavor. Spoon the casserole into bowls while it is hot and finish with plenty of freshly chopped parsley.
Recipe Tips
- Stir the noodles frequently. One-pot pasta contains less free cooking liquid than traditionally boiled pasta, so frequent stirring helps prevent sticking and encourages the sauce to become creamy.
- Check the pasta before the suggested cooking time ends. Different gluten-free pasta blends soften at different rates. Begin testing a noodle a couple of minutes early and stop cooking when the texture suits you.
- Keep the tuna chunky. Fold it into the vegetables gently rather than stirring aggressively. Larger flakes give the finished casserole a better texture.
Can I use regular pasta instead of gluten-free pasta?
Yes, regular shell noodles can work, but their cooking time and liquid absorption may differ from gluten-free pasta. Watch the consistency closely while the noodles simmer. If the pasta becomes tender before enough liquid has reduced, simply continue cooking briefly over gentle heat while stirring.
Why is my tuna casserole too thin?
The sauce naturally thickens as the pasta releases starch and absorbs the broth and coconut milk. If it still looks loose when the noodles are nearly finished, continue simmering uncovered for another minute or two while stirring frequently. The casserole will also thicken slightly after leaving the heat.
Does this casserole taste strongly like coconut?
Full-fat coconut milk supplies the creamy base, so a light coconut flavor may be noticeable depending on the product you use. However, the tuna, chicken broth, garlic, onion, nutritional yeast, pepper, and parsley create plenty of savory flavor to balance it.
Can I make stovetop tuna casserole ahead of time?
You can prepare it ahead, although the texture is at its creamiest immediately after cooking. Gluten-free pasta continues to absorb sauce as it sits, so refrigerated leftovers will usually be thicker. Add a small splash of broth or coconut milk while reheating to loosen the sauce.
How do I know when the gluten-free pasta is done?
Taste a shell near the end of the recommended simmering time. It should be tender throughout without becoming mushy or beginning to break apart. Because gluten-free pasta formulations vary considerably, checking the noodles directly is more reliable than depending only on the clock.
Serving Ideas for Stovetop Tuna Casserole
Because this casserole already contains pasta, tuna, and broccoli, you do not need elaborate sides to turn it into dinner. Keeping the accompaniments simple works especially well.
A crisp green salad makes a refreshing contrast to the creamy pasta. Choose a light dressing so the meal does not become overly rich.
Roasted or sautéed vegetables are another useful option when you want extra produce alongside dinner. Green beans, zucchini, or asparagus all pair naturally with tuna and creamy pasta.
You can also serve the casserole with a simple gluten-free bread or toasted bread alternative for soaking up any creamy sauce remaining at the bottom of the bowl.
How to Store & Reheat
Allow leftovers to cool before transferring them to an airtight container. Store the casserole in the refrigerator for up to 3 days. Because the noodles continue absorbing liquid during storage, the sauce will become noticeably thicker overnight.
For reheating on the stovetop, place the amount you need in a small saucepan over low to medium-low heat. Add a splash of chicken broth or coconut milk and stir regularly until the casserole is creamy and heated through.
You can also reheat individual portions in the microwave. Cover loosely and heat in short intervals, stirring between each interval. Adding a spoonful of broth before reheating helps restore some of the original creamy consistency.
Freezing is possible, but it is not the preferred storage method for this dish because gluten-free pasta may become softer or more fragile after freezing and thawing. If you do freeze leftovers, use an airtight freezer-safe container and keep them for about 1 month. Thaw overnight in the refrigerator before gently reheating with additional broth or coconut milk.
Fresh parsley is best added after reheating rather than before storage. That final scattering of herbs brings back some brightness and gives this creamy one-pot tuna casserole a fresher finish when you serve the leftovers.
Stovetop Tuna Casserole
Ingredients
- 2 cups gluten-free shell-shaped noodles
- 2 tbsp freshly chopped parsley
- 1 1/4 cups full-fat coconut milk
- 3 cloves garlic finely minced
- 2 cans 5 oz each tuna, thoroughly drained
- 1/4 tsp freshly ground black pepper
- 1 –2 tbsp nutritional yeast according to taste
- 1 cup broccoli florets chopped into small pieces
- 2 1/4 cups chicken broth
- 1/2 white onion cut into small dice
- 3/4 tsp salt
- 2 tbsp avocado oil
Instructions
- Heat the avocado oil in a large, deep pot over medium heat until the oil begins to shimmer.
- Add the diced white onion and minced garlic. Sauté for 3–4 minutes, stirring as needed, until the onion becomes lightly translucent.
- Stir in the chopped broccoli and continue cooking for another 3–4 minutes, or until the florets turn vivid green and soften slightly. Season the vegetables with the salt and ground black pepper.
- Add the drained tuna to the pot. Using a wooden spoon, gently break the tuna into smaller pieces while thoroughly combining it with the broccoli and aromatics.
- Pour in the chicken broth and full-fat coconut milk. Stir until the ingredients are evenly distributed, then raise the heat to medium-high and bring the liquid to a gentle boil.
- Add the gluten-free shell noodles once the mixture begins boiling. Reduce to a steady simmer and cook for approximately 10–12 minutes, stirring frequently, until the pasta reaches the desired tenderness.
- During the final minute of cooking, stir continuously to encourage the liquid to reduce and develop a thicker, creamier consistency. For softer noodles, continue simmering for an additional 1–2 minutes.
- Stir in 1–2 tablespoons of nutritional yeast, using the amount that best suits your preferred level of savory, cheese-like flavor.
- Serve the casserole while hot and finish each portion with freshly chopped parsley.
Notes
- For an especially fresh finish and added color, use a generous scattering of parsley immediately before serving.
- If a softer pasta texture is preferred, extend the final simmering time by 1–2 minutes.