Place your roast in the bottom of the Instant Pot.
Add all remaining ingredients on top of roast.
Set Instant Pot to manual and cook on high pressure for 30 minutes. Let pressure do a natural release (it will take about 10-15 minutes).
Remove the roast pieces from the Instant Pot and shred using two forks (it will literally fall apart).
Add pork back into Instant Pot and mix with all the flavorful liquid.
Serve on tortillas and topped with pico de gallo, fresh cilantro, shredded cheese, or your favorite toppings.
Slow Cooker Instructions
Spray your slow cooker with non-stick cooking spray.
Place your roast in the slow cooker. Add all other ingredients (I just dump them in right on top of the roast).
Cook on low for 8-10 hours.
Once finished, shred the roast with two forks (it will literally fall apart).
Serve on flour tortillas for tacos and add desired toppings.
Notes
Tomatillos are like a green tomato wrapped in a husk. When I first purchased one a couple of years ago, I had to ask someone at the grocery store to point them out to me, but I have learned that most grocery stores carry them and they are fairly inexpensive. They are a key ingredient in this pork! Our favorite toppings are: lettuce, tomatoes, salsa, guacamole, sour cream, cheese, green peppers, and jalapeños.