Heat a large pot over medium heat, and add a splash of olive oil.
Add the chopped onion and bell pepper; sauté until tender.
Stir in the minced garlic and sauté for an additional minute.
Add the diced chicken and stir until cooked through.
Pour in the diced tomatoes and chicken broth, followed by the chili powder, cumin, salt, and pepper.
Increase the heat until the mixture reaches a boil, then reduce to a simmer.
Add the corn and lime juice; simmer for an additional 10 minutes.
Serve the soup hot, garnished with cilantro if desired.