In a large bowl, with your hands, mix the ground beef, parsley, almond flour, eggs, salt, onion flakes, pepper, garlic powder, oregano, and water until combined.
Form into 20 meatballs, approximately 2-inches in diameter. Set aside.
Place the avocado oil in the Instant Pot and select “Saute.” When the oil is hot but not smoking, sear 6–7 meatballs at a time, until browned on the tops and bottoms (about 2 minutes per side).*
When all of the meatballs are seared, press “Cancel” and place all of the meatballs back in the bowl of the Instant Pot, layering them, leaving ½-inch space between them.
Pour the marinara sauce over the top.
Secure the Instant Pot lid and select “Manual.” Cook on low pressure for 10 minutes.
When the cooking time is up, carefully move the vent knob to “Venting” to quickly release the pressure.
Serve your meatballs with spaghetti squash (recipe page 9) or zucchini noodles (recipe page 11).
*Alternatively, for the ease of cooking on a flat surface, you can saute your meatballs in a pan on the stove and then transfer them back to the Instant Pot.