Turn the Instant Pot to saute. Cook ground beef, onion and red pepper until beef is browned. Drain any juices.
On saute, add chili powder, salt, garlic and cumin. Cook and stir 1 minute.
Add broth and scrape the bottom to ensure any stuck on bits are removed.
Turn Instant Pot off and stir in beans.
Top with pasta sauce (spread over the top but don't stir) and macaroni. Press pasta down into the liquid and spread into an even layer, but don't stir.
Put the lid on, turn the valve to sealing, and select Pressure Cook or Manual for 2 minutes.
When the cook time is over, do a controlled release of the pressure (slowly release the pressure by holding the valve slightly open but not all of the way).
Remove the lid and stir -- some macaroni may appear dry or stuck together but once you stir it will be perfect.
Stir in milk and cheese until cheese is melted. Serve.