Set the Instant Pot to ‘Sauté’ mode and heat the olive oil.
Add the chicken pieces to the pot and cook for 3-4 minutes, stirring occasionally, until lightly browned but not cooked through. Remove the chicken and set aside.
Add the sliced onion and minced garlic to the pot. Sauté for 2-3 minutes until the onion is softened.
Add the sliced red, yellow, and green bell peppers to the pot. Cook for 2 minutes, stirring occasionally.
Return the chicken to the pot. Pour in the diced tomatoes with their juice and the chicken broth.
Add the dried oregano, smoked paprika, salt, black pepper, and crushed red pepper flakes. Stir to combine all ingredients.
Close the Instant Pot lid and set the valve to ‘Sealing’. Select ‘Manual’ or ‘Pressure Cook’ mode and set the timer for 8 minutes.
When the cooking time is complete, allow the pressure to release naturally for 5 minutes, then carefully perform a quick release to release any remaining pressure.
Open the lid and stir the chicken and peppers. Check seasoning and adjust salt and pepper if needed.
Serve the chicken and peppers hot, alone or over rice or pasta if desired.