In a large pot over medium high heat, add the olive oil. Add the onion and jalapeno and cook until tender, about 5 minutes. Add the garlic, oregano, cumin and chili powder and cook for 1 minute more.
Add the can of green chilis, chicken breasts and chicken broth to the pot. Add salt and pepper. Bring the pot to a boil, reduce the heat and simmer covered for 10 - 12 minutes. The chicken should be tender and cooked through.
Transfer the chicken to a plate and use a fork to shred it into bite-sized pieces. Add it back to the pot along with the white beans and corn. Simmer over low heat, uncovered, for 10 more minutes.
Remove the pot from the heat, stir in the sour cream and squeeze in the juice of 2 limes.
Serve while hot, optionally garnishing with avocado, cilantro, or tortilla chips.
To make this more or less spicy, add more or less green chilis or jalapenos
To make your chili creamier, add an extra spoonful of sour cream or ¼ cup of whole milk