Heat olive oil in a large pot over medium heat.
Add diced onion and sauté until translucent, about 5 minutes.
Stir in minced garlic and chopped jalapeños; cook for 2 minutes more.
Pour in the chicken broth, bringing the mixture to a simmer.
Add the shredded chicken and cubed cream cheese, stirring until the cheese melts.
Mix in the shredded cheddar cheese and chili powder; stir until evenly combined.
Season with salt and pepper to taste, and let simmer for an additional 5-10 minutes.
Stir in sour cream just before serving for added creaminess.
Ladle the soup into bowls and garnish with cilantro.