Using a large bowl, mix together all of the meatball ingredients until well combined. Form into meatballs that are a uniform size.
Heat the avocado oil over medium heat in a large pan and add the meatballs. Cook for about 3-4 minutes on each side, until browned or until the internal temperature reaches 165 F. Set the cooked meatballs aside.
Using the same pan, add more avocado oil to the pan (if needed)and heat. Saute the onion for 5-6 minutes or until soft, adding in the garlic at the end and saute for another minute. Add the mushrooms and cook for another 3-4 minutes or until fork-tender.
Pour in the broth, coconut aminos, ketchup, and seasonings and stir to combine.
Whisk in arrowroot starch and reduce the heat, allowing to thicken for 2-3 minutes.
Once the sauce thickens, add the meatballs back to the pan. Spoon the sauce over the meatballs and simmer for a few minutes to allow to reheat.
Serve topped with chopped parsley and over mashed sweet potato if desired.
Notes
For a premade compliant ketchup, try this for whole30 and this for AIP. I also have an AIP ketchup recipe in my cookbook, The Autoimmune Protocol Comfort Food Cookbook. Note that using an AIP ketchup would not make this dish whole30 as they have sweetener. If you choose to forgo the ketchup, you can try to use nomato sauce instead, and adjust seasonings to taste.All nutritional information are estimations and will vary. Nutritional information does not include optional ingredients.