In a medium-sized mixing bowl, add the ground beef and ground Italian pork sausage. Add the salt and pepper. Mix well using your hands to incorporate the meats and seasonings and parmesan cheese.
Using a 1 oz cookie scoop, scoop the meat and then place in the palm of hands to roll into a meatball. Place on a plate and repeat with all the meat. Set aside.
Heat an Instant Pot on the “saute” function until it says HOT. Add the avocado oil. Add half of the meatballs one at a time and sear them on the first side for 3-4 minutes until browned.
Use a metal spatula to remove them from the pan and flip them, cooking for another 3-4 minutes.
Remove meatballs to a plate and set aside, browning the next batch of meatballs.
Add all meatballs back into the pot.
Add the marinara sauce, sliced garlic, water, and fresh herbs.
Set the Instant Pot to cook on high pressure for 10 minutes using a natural release or quick release.
Serve hot with freshly grated parmesan cheese.