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 / Potato/ Onion Casserole?

You need 9 ingredients. The key ingredients include: 3 tablespoons butter, 2 -3 slices raw onions (thick slices), 3 tablespoons flour, 1 teaspoon salt, and more.

Is Tuna / Potato/ Onion Casserole suitable as seafood?

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

How do I store leftover Tuna / Potato/ Onion Casserole?

Store leftovers in an airtight container in the refrigerator for up to 3–4 days. Reheat gently before serving.

Tuna / Potato/ Onion Casserole Recipe

Name: Tuna / Potato/ Onion Casserole
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 4 servings
Ingredients: 3 tablespoons butter; 2 -3 slices raw onions (thick slices); 3 tablespoons flour; 1 teaspoon salt; 1 teaspoon pepper; 2 cups milk; 1 (7 ounce) can tuna in water, drained; 4 cups quartered potatoes, with skin on; 1 garlic clove, minced

Try this homemade Tuna / Potato/ Onion Casserole recipe the whole family will love. Made with butter, onions, flour and salt. Easy step-by-step instruct…

This Tuna / Potato/ Onion Casserole relies on simple, everyday ingredients such as butter, raw onions (thick slices), flour and salt. It comes together quickly and makes 4 servings, at about 462 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

Servings: persons

3 tablespoons butter
2 -3 slices raw onions (thick slices)
3 tablespoons flour
1 teaspoon salt
1 teaspoon pepper
2 cups milk
1 (7 ounce) can tuna in water, drained
4 cups quartered potatoes, with skin on
1 garlic clove, minced

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Quick Info

Servings
4 servings
Calories
462 kcal
Category
Seafood

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