Wash the bell peppers thoroughly, cut off the tops carefully, and remove all veins using a sharp knife.
In a skillet, heat the oil over medium heat. Add minced garlic and diced onions, sauté until onions are translucent. Add diced carrots and continue to sauté until they soften.
Incorporate the lean ground beef and rice, breaking it into small pieces with a spatula. Cook until browned. Stir in tomato paste, cumin, salt, and pepper. Cook for an additional 2-3 minutes.
Carefully stuff each bell pepper with the prepared filling, ensuring they are packed but not overfilled. Secure the tops of the peppers with wooden toothpicks to prevent unraveling during cooking.
Place the Instant Pot's steamer rack at the bottom. Add 1 cup of water to the Instant Pot. Arrange stuffed bell peppers on the steamer rack. Close the Instant Pot lid, set the steam function, and cook for 8-10 minutes.
Allow the Instant Pot to depressurize naturally before opening. Carefully remove the stuffed peppers using tongs. Sprinkle grated cheese on top for added flavor, texture, and creaminess.