Start off by cutting the chicken breasts into 1-1/2 inch cubes.
Place the meat in a gallon-sized Ziplock bag and add in the curry powder, chili powder, white pepper, garam masala, and salt. Seal the bag and mix well to combine ensuring that each piece has been evenly seasoned with spice rub. Set aside.
Turn the instant pot to "Saute" mode. Pour in the olive oil and allow it get hot, about 3-4 minutes. Add the chopped onions, garlic, and ginger to the hot oil and saute for 2-3 minutes.
Add the seasoned chicken and saute for 5-7 minutes, ensuring you move them around at least once. Once browned, remove and set aside.
Next, add in the coconut milk, Worcestershire sauce, bay leaves, and can of fire-roasted tomatoes. Stir until well combined.
Add the seasoned chicken back in and stir until combined. Turn it off by selecting Cancel. Securely place the lid, ensuring the vent is closed.
Select the Manual mode and set it to cook for 5 minutes on high pressure. After 5 minutes, do a quick release and when the pin drops, remove the lid. The chicken curry sauce will be very liquidy. To thicken, remove 1/2 cup of the sauce and place it in a small bowl. Add 2 Tablespoons of cornstarch to the sauce and whisk until combined.
Set the Instant Pot back to the Saute mode. Slowly pour in the cornstarch mixture and whisk constantly until the the sauce thickens. Once the desired consistency has been met, you are ready to serve.