Start by adding olive oil to a soup pot or dutch oven over medium-low heat. Once the oil is heated, toss in the chopped onion and sauté until it begins to turn translucent. Add minced garlic and cook until fragrant.
Sprinkle in oregano, cumin, salt, pepper, paprika, and cayenne pepper (if using). Sauté these spices for about one minute.
Pour in the chicken stock along with the can of green chiles. Stir everything together thoroughly before increasing the heat until it reaches a low boil.
Reduce the heat and allow the chili to simmer gently without cover for about 25 minutes, stirring occasionally.
Lower the heat slightly again before adding heavy whipping cream, cubed cream cheese, and shredded rotisserie chicken. Cook for another 10–15 minutes while stirring occasionally until everything is heated through and creamy.
Remove from heat and serve hot. You can top your Keto White Chicken Chili with cheese or sour cream based on your preference.