Heat olive oil in a large pot or Dutch oven over medium heat.

Add the diced onion and sauté until softened, about 3-4 minutes.

Stir in the minced garlic and cook for another 1 minute, until fragrant.

Add the shredded chicken, chicken broth, and green enchilada sauce to the pot. Stir to combine and bring to a gentle simmer.

Lower the heat to medium-low and stir in the heavy cream and sour cream until fully incorporated.

Add the shredded Monterey Jack cheese and cheddar cheese gradually, stirring until melted and the soup is creamy.

Season the soup with ground cumin, chili powder, salt, and pepper. Adjust seasoning to taste.

Mix in the corn kernels and black beans and simmer for 5-7 minutes, stirring occasionally.

Remove the soup from heat and garnish with chopped fresh cilantro.

Serve hot with tortilla strips or crushed tortilla chips on top. Optionally, add sliced avocado for extra creaminess.