June 5, 2020

Whole30 Tuna Noodle Casserole

Try our Whole30 spin on a homestyle classic. All of the ingredients for this Whole30 Tuna Noodle Casserole can be found at a “regular” grocery store (no stops to a specialty store required!). It’s a great weeknight dinner meal, and the leftovers are a tasty option for lunch the next day. Enjoy!

Looking for more cozy recipes? Try this Whole30 Cottage Pie with Bison.

Tuna Noodle Casserole
Made By Whole30Made By Whole30

Whole30 Tuna Noodle Casserole

Prep Time 5 minutes
Cook Time 1 hour
Total Time 1 hour 5 minutes



  • 1 cup hot water
  • 1/2 cup cashews salted or unsalted
  • 1 tbsp lemon juice or raw apple cider vinegar
  • 2 tsp sea salt
  • 1/2 tsp black pepper
  • 1 tsp dried dill
  • 1/2 cup chicken broth

Veggies & Tuna

  • 1 tbsp ghee or coconut oil
  • 1 medium yellow onion peeled & diced
  • 2 medium celery stalks diced
  • 3 medium garlic cloves peeled & minced
  • 1 tsp sea salt
  • 1/2 tsp black pepper
  • 1 medium spaghetti squash cooked & skin removed
  • 2 5-oz cans of water-packed tuna drained
  • 1 tbsp coconut aminos
  • 1 tbsp capers
  • 1/4 cup fresh parsley minced
  • 2 tbsp arrowroot powder

Optional Garnish

  • 1/4 cup fresh parsley minced


  • Instant Pot


  • OVEN ROAST spaghetti squash by halving, removing its seeds, and placing on a baking tray in the oven until very soft, about 45 minutes. Alternatively, to cook in your electric pressure cooker, set squash on the steam trivet with 1 cup of water on manual at high pressure with the steam valve sealed for 7 minutes. Release steam after the timer goes off being careful not to burn your hands when removing the squash from the pressure cooker.
  • WHEN soft, carefully shred the squash onto a cutting board.
  • ADD hot water and cashews to a blender and allow to soak for 10 minutes.
  • ADD ghee or coconut oil to a large stockpot or Dutch oven and bring to medium-low heat. Add diced onion, diced celery, minced garlic, sea salt, pepper and dried dill and sauté until soft, about 10 minutes.
  • ADD the remaining sauce ingredients to your blender and blend on high until everything is completely combined. It will have a very thin texture.
  • ADD shredded spaghetti squash to your pot of veggies and gently combine, breaking up the squash “noodles”.
  • ADD your drained tuna and gently combine with the veggies.
  • POUR your sauce into the pot and stir well. With the heat reduced to low, stir in arrowroot powder. This will thicken the sauce substantially.
  • STIR in coconut aminos, capers and minced parsley.
  • HEAT your oven’s broiler and if needed, transfer your casserole to an oven-proof baking dish. Heat under the broiler until the top has formed a golden crust, about 2 minutes, checking after a minute or so to prevent burning.
  • Carefully REMOVE from your oven and allow to cool for a few minutes before serving, garnishing with optional minced parsley.
  • SERVE, storing any leftovers in a glass container in the fridge for 3 days.
Sarah S.

Sarah Steffens

Sarah Steffens, our Recipe Developer, has a B.A. in Business Administration, Public Relations from The Master's University in Southern California. After years of experimenting with nutrition and recipes in her own kitchen, she now works as a Personal Chef and Food Photographer in Sacramento, creating meals that support her client's intention to physically and mentally thrive. She has catered several independent film sets, making it her goal to optimize the energy and well-being of each creative crew. You can find many of Sarah's recipes in various Whole30, Paleo and Keto cookbooks. When Sarah is not cooking and styling recipes, you can find her enjoying a long walk, working on creative projects with loved ones or exploring beautiful Northern California.