Season the chicken thighs with salt, pepper, and garlic powder. Dredge them in flour, shaking off any excess.
Turn on the Instant Pot and select the "Saute" function. Heat the olive oil in the pot and brown the chicken thighs on both sides, working in batches if necessary. Transfer the browned chicken to a plate and set aside.
In the same pot, add the diced onion and sliced red bell pepper. Saute for 3-4 minutes until they begin to soften.
Add the diced tomatoes, tomato paste, black olives, red wine, and capers to the pot. Stir to combine.
Return the browned chicken thighs to the pot, nestling them into the vegetable mixture.
Pour the chicken broth over the chicken and vegetables in the pot.
Close the Instant Pot lid and set the valve to the sealing position. Select the "Pressure Cook" or "Manual" setting and set the timer for 10 minutes on high pressure.
Once the cooking time is complete, allow the pressure to naturally release for 5 minutes, then carefully perform a quick release by turning the valve to the venting position.
Carefully open the Instant Pot lid and check the chicken for doneness. The internal temperature of the chicken should reach 165°F (75°C).
Serve the Instant Pot Chicken Cacciatore hot, garnished with fresh herbs if desired. Enjoy your delicious Italian-inspired meal!