To make the meatballs, beat the egg in a large bowl. Add the breadcrumbs, milk, parsley, Italian seasoning, garlic powder, salt, and pepper, and stir to combine. Add the ground beef and mix again to combine. Form into 16-24 meatballs and set on a plate.
Set InstantPot to ‘sauté’ setting. One hot, add the olive oil. Once shimmering, add the prepared meatballs and cook for 4 to 5 minutes, stirring often, until the meatballs are browned all over. Hit ‘cancel’ to turn the machine off.
Add the broken spaghetti directly on top of the meatballs, doing your best to create an even layer of pasta. Add the marinara and water on top; do not stir.
Add the InstantPot lid and set the valve to ‘seal’. Cook at manual high pressure for 10 minutes. As soon as the cooking timer is up, release the pressure manually.
When you are able to remove the lid, open the pot and gently stir the pasta and sauce so everything is well combined. Serve topped with grated Parmesan and fresh basil.
Notes
Storage: Kept in an airtight container in the fridge, leftovers will last for up to 3 days. I like to reheat the spaghetti and meatballs in the microwave! You can start at a minute or so, adding 30-second increments as necessary.