Place the chopped onion and garlic in a large pot with olive oil. Cook until soft, about 7 minutes.
Add the chicken breasts, potatoes, corn, spices, salsa verde, and chicken broth. Raise the heat to high and bring the chili to a boil.
Reduce the heat to a simmer and place a lid on the pot. Simmer for 30 minutes or until the chicken is cooked through.
Place the cornstarch and water in a small container with a lid and shake well. Drizzle the cornstarch mixture into the chili and stir well until it starts to thicken. Cook for about 5 more minutes.
If you want the chicken cut into even smaller pieces, you can use kitchen shears to do that after it is cooked.
Serve with fresh cilantro, chopped red onion, and tortilla chips.
Notes
Store leftovers in the refrigerator. They should stay fresh for 3-4 days.