Heat the olive oil in a large stockpot over medium-high heat.
Add the chopped onion and cook for 4 minutes, stirring often, until it begins to soften.
Stir in the minced garlic and cook for 1 minute until fragrant.
Add the shredded chicken, chicken stock, creamed corn, drained sweet corn, diced tomatoes with their juices, enchilada sauce, black beans, green chilies, cumin, chili powder, kosher salt, and black pepper.
Bring the soup to a boil over high heat.
Reduce the heat to medium-low and simmer, stirring occasionally, for 30 minutes. Ensure the chicken reaches a safe internal temperature of 165°F (74°C).
Remove the pot from the heat and stir in the heavy cream.
Divide the soup among six bowls and serve with tortilla strips, cilantro, lime juice, sour cream, cheese, and diced avocado.