Set the Instant Pot to Sauté mode and add the olive oil.
Add the diced onion, bell pepper, and jalapeño, sautéing for 3-4 minutes until softened.
Stir in the minced garlic, chili powder, cumin, sea salt, and black pepper, cooking for 1 minute until fragrant.
Add the cubed chicken breast and brown slightly for 2 minutes.
Pour in the chicken broth and use a wooden spoon to scrape any browned bits off the bottom of the pot to prevent a burn notice.
Stir in the rinsed quinoa, black beans, and fire-roasted tomatoes.
Secure the lid and set the Instant Pot to Manual/Pressure Cook on High for 8 minutes.
Once the timer goes off, allow a natural pressure release for 5 minutes, then quick release the remaining steam.
Fluff the casserole with a fork and serve topped with sliced avocado and fresh cilantro.