Salt and pepper chicken. Preheat pressure cooking pot using the saute setting. Add oil, onion, garlic, and chicken to the pot and saute stirring occasionally until onion is softened, about 3 minutes.
Add soy sauce, ketchup, and red pepper flakes to the pressure cooking pot and stir to combine. Pressure cook on high for 3 minutes. When timer beeps, turn pressure cooker off and do a quick pressure release.
Add sesame oil and honey to the pot and stir to combine. In a small bowl, dissolve cornstarch in water and add to the pot. Select Saute and simmer until sauce thickens. Stir in green onions.