In a large pot, heat the olive oil over medium heat. Add the diced onion and sauté for about 5 minutes, until softened. Stir in the minced garlic and cook for an additional 1 minute until fragrant.
Add the cumin, chili powder, smoked paprika, and cayenne pepper (if using) to the pot. Stir well to combine and cook for another minute to toast the spices.
Place the chicken breasts in the pot and pour in the chicken broth. Bring to a boil, then reduce the heat to a simmer. Cover and cook for about 20 minutes, or until the chicken is cooked through.
Remove the chicken from the pot and shred it using two forks. Return the shredded chicken to the pot along with the white beans, diced green chiles, and corn. Stir to combine and let it simmer for another 10 minutes.
Season with salt and pepper to taste. Stir in the sour cream until fully incorporated.
Serve hot, garnished with chopped cilantro and lime wedges on the side.