Add chicken breasts to bottom of slow cooker, top with salt, pepper, cumin, oregano, chili powder, and cayenne pepper.
Top with diced onion, minced garlic, great Northern beans, green chiles, corn, chicken broth and cilantro. Stir.
Cover and cook on LOW for 8 hours or on HIGH for 3-4 hours.
Remove chicken to large mixing bowl, shred, then return to slow cooker.
Add cream cheese and half and half, stir, then cover and cook on HIGH for 15 minutes, or until chili is creamy and slightly thickened.
If you want to ensure a smooth blend of the cream cheese, try adding the softened cream cheese to a small mixing bowl, then adding a few ladles of the chili from the slow cooker. Whisk until smooth, then stir that mixture into the slow cooker and proceed with adding the half and half and cooking on high for 15 minutes.
Stir well and serve with desired toppings.