Vegan Chicken Tetrazzini Casserole is spaghetti that is covered with a rich white sauce. It's sitting on a white plate and is sprinkled with fresh tarragon.
5 from 5 votes

Vegan Chicken Tetrazzini Casserole Recipe

Vegan Chicken Tetrazzini Casserole has a rich white sauce and is a family favorite.
Course Main Dish
Cuisine Pasta
Prep Time 20 minutes
Cook Time 30 minutes
Total Time 50 minutes
Servings 8 Servings
Calories 508kcal
Author Ginny McMeans


  • 1/4 cup dairy free butter
  • 5 tablespoons all-purpose flour - that's 1/4 cup plus 1 tablespoon
  • 1 1/2 cup dairy free milk
  • 1 1/2 cup vegetable broth
  • 11 ounces seitan - you can also make your own seitan
  • 16 ounces spaghetti - uncooked
  • 1 cup dairy free mozzarella cheese - shredded
  • 1 teaspoon sea salt
  • 1/4 teaspoon pepper - I use a mixture of black, white and pink pepper


  • Oil or butter a glass casserole dish. This would do one dish 9" x 13" or do two or three smaller ones. I do the three small ones and freeze two for the future.
  • Break the spaghetti in half before cooking.  In a large saucepan add enough water to generously cover the spaghetti.  Bring the water to a boil.
  • When it comes to a boil add one tablespoon of salt to the water. This is important for the spaghetti to get some seasoning.  Add the spaghetti to the boiling water and cook as directed on the package.  Drain and set aside.
  • Open your package of seitan and cut into small pieces. I put the seitan in a food processor and pulse it about 5 times to chop and shred. Set aside.

Make the roux and sauce:

  • In a large deep skillet, over low heat, melt your butter.
  • When the butter is melted add the flour. Stir over low heat for a couple of minutes to cook the flour mixture.
  • Add the milk and vegetable broth. Cook to a boil but stir often so it doesn't burn. As soon as it comes to a boil turn the heat down to low. Cook for about 10 to 15 minutes.
  • The sauce will also thicken with the addition of the dairy free cheese and seitan.
  • Add the 'cheese' and stir to melt.  Add the seitan and stir.  Season with salt and pepper.  Ad the prepared spaghetti and mix together.
  • Pour into your prepared casserole dish or dishes.  These will keep in your refrigerator for three days.


  • Cover the top of the casserole with the lid or foil and bake in a preheated over at 350° for 20 minutes.  Remove the lid or foil and bake 10 minutes.


Serving: 1Serving | Calories: 508kcal | Carbohydrates: 73g | Protein: 23g | Fat: 15g | Saturated Fat: 3g | Sodium: 926mg | Potassium: 370mg | Fiber: 3g | Sugar: 1g | Vitamin A: 440IU | Calcium: 120mg | Iron: 4.5mg