Add all ingredients for meatballs to a bowl. Mix well. I prefer to use my hands, but you can use a hand mixer or spoon.
You want to make sure the meatballs are on the smaller side, so they cook all the way through. I used a small cookie scoop to measure, and with my hands, rolled into a ball.
Add 1 cup of beef broth to the bottom of your Instant Pot. Place the trivet inside the pot. Add your meatballs evenly on the trivet. You can layer up!
Cook on High Pressure for 7 minutes. Allow it to naturally release for 10 minutes, then manually release until all the pressure is gone.
Remove the trivet with the meatballs on. Set aside on a place or cutting board. Pour out your broth. Turn your Instant Pot onto Sauté mode.
Place your meatballs back in and sauté to make the meatballs nice and crisp for about 4 minutes.
Once done, pour over your sauce, and mix well.
Sliced 1 slice of provolone in half. Place in your bun, one on each side. Add meatballs between the cheese (I used 3 meatballs per sandwich). Microwave for 1 minute or in oven at 350 degrees for about 5 to melt your cheese and warm your bread.
Garnish with Parmesan cheese, and parsley! Enjoy!
Notes
Different Cheese: How about an Italian blend or a good old Mozzarella
More Herbs: How about some fresh basil to top off your sub
Cream Sauce: Try a play on a Swedish meatball sandwich