Preheat a small frying pan over medium heat. Once warm, add coriander, cinnamon, star anise, cardamom and black pepper corns. Cook for 1 - 2 minutes, just enough to begin releasing their natural oils.
Place the spice mixture, minus the cinnamon, in a spice ball, cheesecloth, tea bag, or anything else you can use to make a spice pouch.
Turn the 6 qt Instant Pot on to saute. When warm, add oil, ginger/garlic masala and onions. Saute for 2 - 3 minutes.
Turn off the Instant Pot. Add the water, spices from Step 2, cinnamon, chicken, fish sauce, brown sugar and sriracha. Cook on High Pressure for 20 minutes (25 minutes if cooking the chicken from frozen). Natural release pressure. If you're doubling this recipe, you could wait up to an hour for all of the pressure to naturally release. After 10 minutes, you can quick release the remaining pressure.
Using a slotted ladle, remove the chicken and onions. You may need a fine-mesh strainer to remove smaller pieces of onion. Remove the spice pouch and cinnamon, Discard the onions and spices. Let the chicken cool for a bit before removing the meat from the bones. Discard the chicken skin and bones. Add the chicken back to the stock.