Add other soup ingredients to blender (except for tapioca starch and water) and blend well. Add to instant pot.
Close lid, turn steam valve to "sealing." Turn IP on high pressure and set to 10 minutes.
Once cooking is complete, allow steam to naturally release by opening the steam valve. Once steam release is complete, carefully open lid.
Make a slurry with 3 tbsp tapioca starch and 1/4 cup water and add to soup. Stir.
While soup thickens, shred the chicken with 2 forks. You can do this in the pot or take the chicken out and shred it on a plate, then add back to IP.
Garnish with fresh avocados and serve.
Notes
Vegan Adaptation: Omit chicken and add any other desired igredientsFor frozen chicken, add 3-5 minutes to cook time.Store in the refrigerator for 3-4 days in a tightly sealed container.