In large stock pot heat oil and sauté onion until softened before adding garlic, diced pepper, green chilies, salt, pepper, cumin, chili powder, and oregano.
Once peppers are softened but not fully cooked add chicken stock and chicken breasts and bring to a boil. Once boiling reduce the heat to a simmer and cook for an additional 8-15 minutes until chicken is done and shreds easily.
Put all the soup ingredients in the crock-pot including seasonings but not toppings cook on high for 3 hours or on low for 6 hours.
Put all the soup ingredients in the instant-pot including seasonings but not toppings cook on high pressure for 12 minutes.
Shred chicken before serving with any or all the above-listed toppings