How many servings does this recipe make?

This recipe makes 4 servings. You can adjust the portion size directly on this page.

What ingredients do I need for Tuna Salad Casserole?

You need 10 ingredients. The key ingredients include: 2 cans tuna, drained, 1 1/2 c. celery, diced, 1 can mushrooms, drained, 1/2 c. ripe olives, sliced, and more.

Is Tuna Salad Casserole suitable as seafood?

Yes, Tuna Salad Casserole falls under the Seafood category and is a great choice for this type of meal.

How do I store leftover Tuna Salad Casserole?

Keep refrigerated in an airtight container and enjoy within 1–2 days for the best freshness. Best served cold — no reheating needed.

Tuna Salad Casserole Recipe

Name: Tuna Salad Casserole
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 4 servings
Ingredients: 2 cans tuna, drained; 1 1/2 c. celery, diced; 1 can mushrooms, drained; 1/2 c. ripe olives, sliced; 1 Tbsp. onion, grated; 1 tsp. lemon juice; 1 c. mayonnaise; 2 c. Corn Chex; 1/2 c. Cheddar cheese, shredded; 1 Tbsp. butter, melted

Fresh, crisp and full of flavor — this Tuna Salad Casserole is a must-try. Made with tuna, celery, mushrooms and ripe olives. Easy step-by-step instruct…

This Tuna Salad Casserole relies on simple, everyday ingredients such as tuna, drained, celery, diced, mushrooms, drained and ripe olives, sliced. It comes together quickly and makes 4 servings, at about 927 kcal each. The step-by-step instructions below are written to be easy to follow, even on a busy day.

It's versatile enough for an easy weeknight dinner yet satisfying enough for guests at the weekend. Serve it with your favorite sides, and keep any leftovers for a quick meal the next day.

Updated Jun 30, 2026

Serves 4 Seafood

Tips for the best results

Read through all the steps once before you start and measure out your ingredients first — it makes everything go more smoothly.
Taste as you go and adjust the seasoning before serving.
Avoid overcrowding the pan — cook in batches if needed for the best texture.
Let the dish rest for a few minutes before serving so the flavors settle.
Store leftovers in an airtight container in the fridge and enjoy within a few days.

Variations & substitutions

Use a neutral oil or a plant-based spread in place of butter for a dairy-free version.

No specific allergen information. Please check the ingredient list for possible allergens.

My Personal Notes

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Tuna Salad Casserole

Tips for the best results

Variations & substitutions

My Personal Notes

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