Place chicken, vegetables and seasonings except fish sauce in Instant Pot bowl.
Cover and seal pot making sure vent knob is set on sealed
Select poultry or manual cook mode
Adjust cooking time to 30 minutes using the +/- timer
When Instant Pot beeps the cooking cycle is complete. Carefully release pressure by moving top knob from sealing to venting.
Once pressure is released, uncover.
Remove chicken and potato chunks and reserve in bowl.
Add fish sauce to pot. If you have an immersion blender, puree vegetables in Instant Pot to desired consistency or spoon vegetables and liquids into a blender to puree.
Shred chicken
Add potatoes and chicken to pureed sauce.
Serve with warm corn or flour tortillas
Garnish with cilantro, shredded cabbage, avocado
Yum!