Whisk the ketchup, honey, brown sugar, soy sauce, garlic and water in the Instant Pot. Set it to Sauté and stir until it just bubbles, scraping the bottom of the pot, then press Cancel.
Pour the frozen meatballs on top of the sauce and spread them out. Don't stir them down to the bottom.
Lock the lid, set the valve to Sealing and cook on High Pressure for 5 minutes. Let the pressure release naturally for 5 minutes, then quick release the rest.
Stir, then set it to Sauté for 2 to 3 minutes, stirring the whole time, until the sauce is thick and coats the meatballs and the meatballs are 165°F in the center. Top with green onions and serve.
Notes
This recipe is written for fully cooked frozen meatballs. Don't thaw them first.Makes about 64 small meatballs, about 4 per serving.If you see the BURN warning, press Cancel, release the pressure, scrape the bottom of the pot, add 1/4 cup more water and start again.