Put the chicken, chili powder, garlic powder, cumin, chicken broth, and tomatoes in the instant pot. Be sure to include the water from the canned tomatoes as well.
Cover your instant pot and set to pressure cook for 20 minutes. If you're using frozen chicken breasts, set it for 30 minutes.
When the chicken is done cooking, allow the cooker to vent and depressurize and then cover the pot. To create shredded chicken tacos instant pot, use a fork to shred the chicken. It can be easier to shred it with two forks rather than one.
Serve your chicken in tortillas and topped with whatever toppings you like, including cheese, guacamole, tomatoes, sour cream, and more.