Dice the chicken breasts in to bite size pieces. Season with salt and pepper and mix well.
In a medium size mixing bowl, mix together orange juice, apple cider vinegar, soy sauce, ketchup, brown sugar, maple syrup, and red pepper flakes.
Set Instant Pot to Sauté on high heat by pressing “sauté” button twice. Sauté chicken in three batches for about 5 minutes, until golden color. After the chicken is done, scoop it out to a different bowl.
Add sautéed chicken back to Instant Pot and add orange marinade.
Cover with a lid and cook on Manual high pressure for 7 minutes. Make sure that the venting knob is turned to “Sealing”!
When it is done, let it naturally release the pressure for 5 minutes. Then switch the knob to venting position and release the steam. Make sure the steam is fully released and the valve is completely down before opening the pot!
Set the Instant Pot to sauté again. As soon as the liquid starts boiling, add 2 tablespoons of cornstarch mixed with ¼ cup of water. Continue to boil until the sauce thickens to the right consistency.