Marinate Chicken: Mix all the ingredients mentioned above in the "Homemade Spice Mix" section in a small bowl. Dice the skinless, boneless chicken breasts or thighs into ½ or 1 inch cubes and add half of the homemade spice mix. Coat the chicken pieces well and marinate for 30 mins. If you are in a hurry skip marinating.
Sear Chicken: Set the instant pot on SAUTE setting & keep it on HIGH heat. Add the oil and when the oil becomes really hot gently release the marinated chicken and sear well until the chicken pieces turn golden around the edges. Set them aside.
Saute aromatics: In the same pot add the diced onion & saute for 1 min. Now, add the ginger & garlic and saute until the onion begins to turn soft.
Saute homemade spice mix: Reduce the heat to LOW setting otherwise the spice mix might burn. Now, add the rest of the homemade spice mix and saute for 2 mins. The spices will release essential oils and become so aromatic.
Deglaze pot: Now, pour the chicken stock (better than bouillon chicken base diluted in warm water) and deglaze the pot very well with the help of a spatula scraping the sides & the bottom of the pot. This will help loosen any stuck food particles & prevent the BURN error. This step is super important, DO NOT rush!
Prep peanut butter sauce: Now, add the smooth peanut butter, ketchup & brown sugar and stir very well to completely dissolve the peanut butter to form a smooth curry sauce. There should not be any lumps at all. This will also help prevent the BURN!
Pressure Cook: Cancel the SAUTE function. Transfer back the seared chicken & the diced veggies into the instant pot. Stir to mix well. Secure the lid of the instant pot, seal the valve & PRESSURE COOK on high for just 2 mins. Once the cooking cycle is over the instant pot will begin to beep, perform a quick pressure release immediately by manually moving the valve from the sealing to the venting position. Open the lid carefully when the metal pin on the lid drops. Give everything a good stir!
Serve: Now, add the dry roasted peanuts & save a few for garnish. Mix well. Serve the Thai Peanut chicken curry with steamed white Jasmine rice for best flavor. Enjoy!