Set Instant Pot to Saute. When the display reads HOT add the ground beef and diced onion to the pot.
Cook and crumble until ground beef is almost cooked through, about 5 minutes.
Add garlic and cook about 1 minute or until fragrant.
Pour in 1/4 c. of beef broth and scrape the bottom of the pot to release any pieces of beef that may be stuck to the bottom of the pot. This will prevent the burn indicator on the instant pot when pressure cooking.
Add the rest of the broth, diced tomatoes, tomato sauce, kidney beans, brown sugar, chili powder, cumin, salt, ground black pepper and macaroni. Stir and make sure the macaroni is submerged into the broth.
Lock the lid, seal the valve and set the pressure cooking time to 5 minutes, high pressure.
When instant pot is done cooking, quick release the steam valve.
Remove the pot from the Instant Pot and stir in the cheese until completely melted and combined.
Let set for five minutes to thicken and then serve.