Select the brown/sauté setting on the Instant Pot. Add olive oil to the bottom of the Instant Pot. Add diced onion and cook with the lid off, about 5 minutes.
Add L&B Deli Tomatillo Verde Sauce, cannellini beans, Great Northern beans, pinto beans, chili powder, cumin, salt, chicken and chicken broth; stir well to combine.
Shut the lid of the Instant Pot and close the steam valve. Cook on high pressure for 15 minutes.
Follow the Instant Pot directions for Natural Release, allowing the pressure in the pot to release slowly for about 10 minutes. Then follow the instructions for Quick Release, allowing the pressure to release completely.
Remove the chicken breasts, shred with two forks, and return to the pot, stirring to combine.
Top with cilantro or other favorite toppings, like jalapeño, shredded cheese, chopped green onion, sour cream or plain Greek yogurt. Enjoy!