Cut the chicken breasts into bite-size pieces.
Add the oil, minced onion and minced garlic to the Instant Pot insert.
Turn on Saute mode and toss the chicken pieces with the oil, onion and garlic for 3 to 5 minutes, or until the chicken begins to cook on the edges. It will finish cooking during the pressure cook cycle.
Pour in the dry rice and broth, and gently stir to get all the rice underwater.
Put the lid on and set to Sealing.
Cook on High, for 7 minutes.
Let naturally release.
Chop the broccoli into bite size pieces/florets.
Fluff the rice and chicken, then stir in the butter, cheese and broccoli. Leave on warm mode for 5 minutes to let broccoli steam up. If you want it to be creamier, you can add 3-4 Tbsp milk. Season with salt and pepper to taste.
Serve Instant Pot Chicken, Broccoli and Rice, as one dish meal or with side salad.