Tuna Mushroom Casserole

Tuna Mushroom Casserole is an old-fashioned comfort food classic made with tender egg noodles, flaky tuna, and a creamy mushroom sauce topped with buttery cracker crumbs. This easy baked casserole brings together simple pantry ingredients to create a hearty, nostalgic meal that is perfect for busy weeknights.

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Why You’ll Love This Tuna Mushroom Casserole

Cream of mushroom soup and milk create a smooth, creamy sauce that coats the noodles, tuna, and mushrooms evenly for a balanced bite in every spoonful. A buttery saltine cracker topping bakes into a crisp golden crust that contrasts perfectly with the creamy casserole underneath.

Equipment You’ll Need

• Large pot for cooking noodles
• 9×13 baking dish
• Large mixing bowl
• Medium mixing bowl
• Whisk
• Measuring cups and spoons
• Colander for draining noodles
• Small bowl for cracker topping

Ingredients for Tuna Mushroom Casserole

For the Casserole Base:

• Egg noodles – Provide the hearty foundation of the dish while absorbing the creamy sauce without becoming mushy
• Canned tuna – Delivers protein and that distinctive savory flavor that makes this casserole a classic comfort food
• Canned mushrooms – Adds an earthy, umami flavor and meaty texture that complements the tuna perfectly
• Milk – Creates richness and helps thin the soup to the perfect creamy consistency
• Cream of mushroom soup – Acts as the binding agent that creates the creamy sauce while intensifying the mushroom flavor
• Salt – Enhances all the flavors in the dish and balances the creaminess
• Pepper – Adds subtle warmth and depth to the overall flavor profile

For the Crispy Topping:

• Saltine crackers – Creates a crisp, golden crust that contrasts beautifully with the creamy filling
• Butter – Helps the crackers brown while adding rich flavor to the topping

How to Make Tuna Mushroom Casserole

1. Preheat your oven to 350°F (175°C) and lightly grease a 9×13-inch baking dish.
2. Bring a large pot of salted water to a boil.
3. Add 8 ounces of egg noodles to the boiling water and cook according to package directions until al dente, usually 6-8 minutes.
4. While the noodles cook, drain two 6-ounce cans of tuna, flaking the meat with a fork.
5. Drain one 8-ounce can of mushrooms, reserving 2 tablespoons of the liquid for added flavor.
6. In a medium bowl, whisk together one 10.5-ounce can of cream of mushroom soup with 1 cup of milk until completely smooth.
7. Season the soup mixture with ½ teaspoon salt and ¼ teaspoon black pepper, adjusting to taste.
8. After you have the creamy mushroom sauce combined, you will want to mix it with the noodles.

Assembling the Casserole:

1. In a large mixing bowl, combine the hot cooked noodles, flaked tuna, and drained mushrooms.
2. Pour the reserved mushroom liquid over the mixture.
3. Add the creamy soup mixture to the bowl and gently fold until all ingredients are evenly coated.
4. Transfer the mixture to your prepared baking dish, spreading it evenly.

Creating the Topping:

1. Crush approximately 15-20 saltine crackers (about 1 cup crushed) in a small bowl.
2. Melt 2 tablespoons of butter and pour over the crushed crackers.
3. Toss the crackers and butter together until all crumbs are lightly coated.
4. Sprinkle the buttered cracker mixture evenly over the top of the casserole.

Baking:

1. Place the casserole in the preheated oven, uncovered.
2. Bake for 25-30 minutes until the topping is golden brown and the edges are bubbling.
3. Allow the casserole to rest for 5 minutes before serving to set the creamy sauce.

Tips for Perfect Tuna Mushroom Casserole

• Noodle Choice: While egg noodles are traditional, you can substitute rotini, penne, or any medium pasta shape you have on hand.
• Tuna Selection: For the best flavor, choose tuna packed in water rather than oil, and solid white albacore tuna provides the most substantial texture.
• Mushroom Varieties: While the recipe calls for canned mushrooms, you can substitute 8 ounces of fresh mushrooms sautéed in butter until golden for an even more intense mushroom flavor.
• Creaminess Control: For a thicker casserole, reduce the milk to ¾ cup; for a looser consistency, increase to 1¼ cups.
• Make it Ahead: You can assemble the casserole up to the baking stage, cover, and refrigerate for up to 24 hours. Add the cracker topping just before baking and add 5-10 minutes to the baking time.

Make-Ahead, Storage, and Reheating Instructions

Make-Ahead:

Prepare the casserole up to the point of baking, cover with plastic wrap or aluminum foil, and refrigerate for up to 24 hours. When ready to bake, remove from the refrigerator while the oven preheats, add the cracker topping, and bake as directed, adding 5-10 minutes to account for the chilled temperature.

• Refrigerator Storage: Store leftover tuna mushroom casserole in an airtight container in the refrigerator for up to 3 days.

• Reheating Method: Reheat individual portions in the microwave until heated through, or warm the casserole in a 325°F oven for about 15 to 20 minutes. Cover loosely with foil if the topping begins to brown too quickly.

• Freezing: Freeze the casserole in a freezer-safe container for up to 2 months. Thaw overnight in the refrigerator and reheat in the oven until warmed through.

Are you looking for more great tuna recipes? Be sure to check out these, where tuna is the star attraction.

• Cheesy Tuna Noodle Casserole
• Grilled Tuna and Cheese Sandwich
• Subway Tuna Salad Sandwich
• Tuna Stuffed Crescent Roll Casserole

Check out more of my easy casserole recipes to make for breakfast, lunch, or dinner.

Common Questions and Troubleshooting

Can I use fresh tuna instead of canned?

While fresh tuna steaks are delicious, they’re actually not ideal for this casserole. The texture and flavor of canned tuna are what give this dish its classic appeal. If you want to use fresh fish, poached white fish like cod would work better than fresh tuna.

My casserole seems dry. What went wrong?

Egg noodles can absorb a lot of liquid. If your casserole seems dry, mix a little more milk (about ¼ cup) with a tablespoon of cream of mushroom soup and gently fold it into the casserole before baking.

Can I make this casserole in advance and freeze it?

Yes! Assemble the casserole without the cracker topping, cover tightly, and freeze for up to 3 months. Thaw overnight in the refrigerator, add the cracker topping, and bake as directed, adding 10-15 minutes to the baking time.

My family doesn’t like mushrooms. Can I omit them?

Absolutely. You can substitute cream of celery soup for the cream of mushroom and omit the canned mushrooms. Add a cup of frozen peas or chopped celery for texture and flavor.

Dietary Modifications and Substitutions

• Gluten-Free Option: Use gluten-free pasta and ensure your cream of mushroom soup is gluten-free. Substitute gluten-free crackers or crushed potato chips for the saltine topping.
• Dairy-Free Alternative: Use unsweetened almond or oat milk and a dairy-free cream of mushroom soup. Replace butter with olive oil for the topping.
• Higher Protein Version: Add an extra can of tuna and mix in ½ cup of cottage cheese with the soup mixture.
• Vegetable Boost: Mix in 1 cup of frozen peas and carrots or sautéed bell peppers when combining the noodles and sauce.