Tuna Green Bean Casserole

green beans casserole
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Ratings (4)
  • Total: 50 mins
  • Prep: 15 mins
  • Cook: 35 mins
  • Yield: 4 to 6 servings
Nutritional Guidelines (per serving)
297 Calories
11g Fat
24g Carbs
24g Protein
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

This simple tuna and vegetable casserole comes together with a simple white sauce. Frozen cooked green beans, tuna, and diced celery make a tasty casserole with relatively few carbs. If you aren't counting carbs, serve the casserole with some hot cooked rice or noodles.

Canned or fresh sauteed mushrooms are another possibility for extra flavor and texture. For an all-in-one casserole, spread a layer of cooked rice—about 1 1/2 to 2 cups—in the prepared baking dish before you add the tuna and green bean mixture.

Top the casserole off with some crumbled French fried onions if you'd like, or sprinkle about 1/2 cup of buttered breadcrumbs over the top before it goes into the oven.


  • 2 tablespoons butter
  • 3 tablespoons all-purpose flour
  • 1/2 teaspoon salt
  • 1/4 teaspoon pepper
  • 1 1/3 cups milk
  • 2 (7-ounce) cans tuna (drained, juice reserved)
  • 1/2 teaspoon dried thyme
  • 1/2 cup celery (finely diced)
  • 1 1/2 cups green beans (fresh or frozen cooked)

Steps to Make It

  1. Heat the oven to 350 F. 

  2. Lightly butter a 1 1/2-quart baking dish (11-by-7-inch baking pan or 8-inch square baking dish).

  3. In a medium saucepan, heat 2 tablespoons of butter; blend in the flour, salt, and pepper. Stir until smooth. Continue to cook for 2 minutes while stirring constantly.

  4. Gradually add the milk and continue to cook until thickened, stirring constantly.

  5. Add the dried thyme, tuna, reserved juice from the tuna, celery, and green beans; mix well.

  6. Transfer tuna and green beans to the prepared baking dish and bake for 25 to 30 minutes.

  7. Serve the casserole with hot cooked rice or noodles, if desired.