Set a large 6-8 quart soup pot (or dutch oven) over medium heat. Add the oil and chopped onions. Saute the onions for 2-3 minutes, stirring. Then add in the garlic, jalapeno, cilantro, cumin, oregano, and cayenne pepper. Saute another 2-3 minutes to soften.
Add the chicken broth, whole chicken breasts, and chopped green chiles to the pot. Season with 1 teaspoon salt and 1/4 teaspoon ground black pepper. Bring to a boil. Then simmer for 20 minutes until the chicken is cooked through.
Meanwhile, cut the corn off the cobs and set aside.
Use tongs to remove the cooked chicken from the pot. Add the corn, to the pot and stir. Then chop or shred the chicken breasts, and place the meat back into the pot.
Stir in the sour cream and shredded cheese. Stir rapidly as you sprinkle the cornstarch over the top of the chili. (Stirring fast helps reduce clumps.)
Simmer for 3-5 minutes until the chili base thickens. Then turn off the heat and stir in the lime juice. Ladle into bowls and serve with your favorite garnishes.
Frozen Corn - Yes, you can use frozen corn instead of fresh corn cobs. Yet fresh always tastes better!