Tuna Mushroom Casserole

Growing up as an only child, our weeknight dinners needed to be three things: affordable, filling, and something that would create leftovers for busy days ahead. The night my mother first made her special tuna casserole—the one with extra mushrooms—I fell silent, savoring each creamy, comforting bite. My dad, who rarely commented on meals, said it reminded him of his mother’s cooking. That evening, as we enjoyed second helpings around our small family table, a cherished tradition was born.

Why You’ll Love This Tuna Mushroom Casserole

• Budget-Friendly – Using pantry staples like canned tuna and mushrooms makes this an economical meal option that doesn’t sacrifice flavor
• Time-Saving – Ready in under an hour with minimal hands-on preparation time
• Crowd-Pleasing – The familiar, comforting flavors appeal to both adults and children
• Versatile – Easy to adapt with whatever ingredients you have on hand
• Make-Ahead Friendly – Perfect for meal prep and actually tastes even better the next day

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 – Provides 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

• Preheat your oven to 350°F (175°C) and lightly grease a 9×13 inch baking dish.
• Bring a large pot of salted water to a boil.
• Add 8 ounces of egg noodles to the boiling water and cook according to package directions until al dente, usually 6-8 minutes.
• While the noodles cook, drain two 6-ounce cans of tuna, flaking the meat with a fork.
• Drain one 8-ounce can of mushrooms, reserving 2 tablespoons of the liquid for added flavor.

• In a medium bowl, whisk together one 10.5-ounce can of cream of mushroom soup with 1 cup of milk until completely smooth.
• Season the soup mixture with ½ teaspoon salt and ¼ teaspoon black pepper, adjusting to taste.

After you have the creamy mushroom sauce combined, you will want to mix it with the noodles.

Assembling the Casserole:

• In a large mixing bowl, combine the hot cooked noodles, flaked tuna, and drained mushrooms.
• Pour the reserved mushroom liquid over the mixture.
• Add the creamy soup mixture to the bowl and gently fold until all ingredients are evenly coated.
• 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.

Storage:

Leftover casserole can be stored in an airtight container in the refrigerator for up to 3 days. For individual portions, divide into microwave-safe containers for quick lunches or dinners throughout the week.

Reheating:

For best results, reheat individual portions in the microwave for 2 minutes at 70% power, stirring halfway through. For larger portions, cover with foil and reheat in a 325°F oven for 15-20 minutes until heated through. Add a splash of milk if it seems dry before reheating..

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

• Creamy Tuna Noodle Casserole
• Grilled Tuna and Cheese Sandwich
• Tuna Stuffed Crescent Roll Casserole

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 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.