Crockpot Tuna Casserole

Tuna casserole in the CROCKPOT, hear me out. Egg noodles, cream of mushroom soup, melty cheddar on top, frozen peas dumped in together and left alone for a few hours.

You barely lift a finger and somehow dinner is the best thing you eat all week. Set it and forget it, but make it TUNA.

Why Make Tuna Casserole in a Crockpot?

• HANDS OFF cooking means no babysitting the oven while it runs
• Slow, gentle heat MELTS the cheese into every noodle crevice (the oven just can’t compete)
• FLAVORS meld together without drying anything out, which is the #1 casserole complaint
• ONE pot from start to finish equals fewer dishes and more sanity
• Built for BUSY weeknights or lazy Sundays when dinner needs to basically make itself
• The noodles drink up that creamy mushroom broth like a sponge…. in the BEST way

Bottom line: the crockpot takes a basic casserole and makes it cozy, hands-free, and foolproof. Toss it in, walk away, and come back to dinner done right.

How to Nail the Noodle Texture

Undercook those noodles on the stovetop… aim for AL DENTE because they will absolutely finish cooking in the slow cooker. Overcooked noodles turn into mush (and nobody wants sad, soggy pasta).

Stir the casserole GENTLY once or twice during cooking so the noodles don’t clump or stick to the bottom. Trust the LOW heat setting to do the heavy lifting, HIGH will turn everything into a gluey mess!

How to Get a Crispy Breadcrumb Topping

Step 1: Hold off on the breadcrumbs until the casserole is DONE cooking. Crockpots trap moisture, and moisture is the sworn enemy of anything crispy. (Adding them early guarantees soggy sadness.)

Step 2: Toast the dry breadcrumbs in a dry skillet over medium heat for 2 to 3 minutes. Stir often. You’re looking for golden brown and fragrant, not burnt.

Step 3: Sprinkle the toasted breadcrumbs over the melted cheese layer RIGHT before serving. Use your judgement on how much, but a thin, even coat gives you crunch in every bite.

Step 4: Serve IMMEDIATELY. Don’t cover the pot, don’t let it sit. The longer it rests, the more steam sneaks back into those crumbs.

The contrast of creamy casserole against that buttery toasted crunch? That’s the whole point. Don’t waste it by getting impatient with the timing!!

Storage & Reheating Tips

• REFRIGERATE PROMPTLY – Airtight container, 3 to 4 days MAX. Tuna doesn’t play around (your nose will tell you when it’s done)!
• FREEZE WITH CAUTION – Cream and noodles get grainy when thawed. Texture suffers, but it’s still edible (better than takeout, just not photogenic).
• REHEAT GENTLY – Microwave at 70% power in 1-minute bursts, stirring between. Prevents noodle mush.
• ADD BROTH WHEN REHEATING – The noodles absorb the sauce as it sits (….). Stir in 1 to 2 tablespoons of chicken broth to loosen things up.
• OVEN WORKS TOO – 350°F, covered with foil, 20 minutes. Uncover the last 5 minutes to re-crisp the topping.

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2000-2200
• Protein: 110-125 g
• Fat: 45-55 g
• Carbohydrates: 270-300 g

Ingredients

For the casserole:

• 12 oz uncooked egg noodles
• 1 can (10.5 oz) condensed cream of mushroom soup
• 2 cups chicken broth for slow cooker or 3.5 cups for pressure cooker
• 1 cup diced onion
• 3 cans (5 oz each) tuna, drained
• 2 tbsp italian blend seasoning
• 1/2 tsp salt
• 1/2 tsp ground black pepper
• 8 oz canned mushrooms, sliced and drained
• 1 1/2 cups frozen peas

For the topping:

• 1 cup shredded cheddar cheese
• Optional: 1/4 cup dry breadcrumbs

Step 1: Boil the Egg Noodles

• 12 oz uncooked egg noodles

Bring a large pot of salted water to a boil.

Add the egg noodles and cook according to package instructions until just a little underdone (al dente).

Drain well and set aside for later use.

I always make sure not to overcook the noodles, as they’ll finish cooking in the casserole.

Step 2: Combine the Sauce and Tuna

• 1 can (10.5 oz) condensed cream of mushroom soup
• 2 cups chicken broth
• 3 cans (5 oz each) tuna, drained
• 1 cup diced onion
• 2 tbsp Italian blend seasoning
• 1/2 tsp salt
• 1/2 tsp ground black pepper
• cooked egg noodles (from Step 1)

In a large bowl, whisk together the cream of mushroom soup and 2 cups of chicken broth until smooth and creamy.

Add in the drained tuna, diced onion, Italian seasoning, salt, and black pepper.

Stir until everything is well combined.

Then gently fold in the undercooked noodles (from Step 1) until evenly coated with the sauce.

Step 3: Slow Cook to Blend Flavors

Transfer the noodle mixture into your slow cooker.

Cover and cook on LOW for 3 to 4 hours or on HIGH for 1½ to 2 hours, stirring occasionally if possible, until everything is heated through.

This gentle cooking blends the flavors beautifully.

Step 4: Fold in Veggies and Cheese

• 8 oz canned mushrooms, sliced and drained
• 1 1/2 cups frozen peas
• 1 cup shredded cheddar cheese

15 minutes before the cook time ends, lift the slow cooker lid.

Gently fold in the sliced mushrooms (drained) and frozen peas.

Stir in ½ cup of the shredded cheddar cheese until mixed throughout the casserole.

Top the casserole with the remaining ½ cup of cheese and replace the lid, allowing the cheese to melt into the casserole for the final 15 minutes.

I like to let the cheese bubble just a bit for extra flavor.

Step 5: Finish with Breadcrumbs

• optional: 1/4 cup dry breadcrumbs

Once the cheese is melted and the casserole is hot, sprinkle the top with dry breadcrumbs just before serving, if desired.

Serve hot and enjoy!

One-Pot Crockpot Tuna Casserole

Delicious One-Pot Crockpot Tuna Casserole recipe with step-by-step instructions.

Print Recipe Pin Recipe

Prep Time 1 hour hr

Cook Time 2 hours hrs 2 minutes mins

Total Time 3 hours hrs 2 minutes mins

Servings: 4

Calories: 2100

Ingredients Method

Ingredients

  

For the casserole:

• 12 oz uncooked egg noodles
• 1 can (10.5 oz) condensed cream of mushroom soup
• 2 cups chicken broth for slow cooker or 3.5 cups for pressure cooker
• 1 cup diced onion
• 3 cans (5 oz each) tuna, drained
• 2 tbsp Italian blend seasoning
• 1/2 tsp salt
• 1/2 tsp ground black pepper
• 8 oz canned mushrooms, sliced and drained
• 1 1/2 cups frozen peas

For the topping:

• 1 cup shredded cheddar cheese
• optional: 1/4 cup dry breadcrumbs

Method

 

1. Bring a large pot of salted water to a boil. Add the egg noodles and cook according to package instructions until just a little underdone (al dente). Drain well and set aside for later use. I always make sure not to overcook the noodles, as they'll finish cooking in the casserole.
2. In a large bowl, whisk together the cream of mushroom soup and 2 cups of chicken broth until smooth and creamy. Add in the drained tuna, diced onion, Italian seasoning, salt, and black pepper. Stir until everything is well combined. Then gently fold in the undercooked noodles (from Step 1) until evenly coated with the sauce.
3. Transfer the noodle mixture into your slow cooker. Cover and cook on LOW for 3 to 4 hours or on HIGH for 1½ to 2 hours, stirring occasionally if possible, until everything is heated through. This gentle cooking blends the flavors beautifully.
4. 15 minutes before the cook time ends, lift the slow cooker lid. Gently fold in the sliced mushrooms (drained) and frozen peas. Stir in ½ cup of the shredded cheddar cheese until mixed throughout the casserole. Top the casserole with the remaining ½ cup of cheese and replace the lid, allowing the cheese to melt into the casserole for the final 15 minutes. I like to let the cheese bubble just a bit for extra flavor.
5. Once the cheese is melted and the casserole is hot, sprinkle the top with dry breadcrumbs just before serving, if desired. Serve hot and enjoy!