Start up the sauté function on the Instant Pot (keep it to low or medium since hot tends to get too hot). Heat the oil in the pot.
When the oil is hot, add the chopped scallions, bell peppers, mushrooms, and garlic. Let everything simmer for about 2 minutes, stirring occasionally,
Add the rice into the Instant Pot and let the rice toast for about a minute or two, stirring occasionally. Add the onion powder, garlic powder, and a sprinkle of salt.
Finally, pour the broth and soy sauce into the pot.
Give everything one last quick stir, and secure the lid on the Instant Pot. Set the valve to the Sealing position and cook the rice on high pressure for 4 minutes. When ready, let the pressure release naturally for 5 minutes. After 5 minutes, if needed, do a quick release. Unlock the lid, fluff the rice with a fork, and let it stand for about 5 minutes before serving.