Chop onion and mince garlic. Heat oil in a large stock pot over medium. Add onion, cook for 3 minutes. Add garlic and cook for 30 seconds more.
Pour in chicken broth; add cumin, chili powder, paprika, salt, and pepper. Stir.
Pull chicken from bones, shred, and add to the pot; bring to a boil.
Reduce heat, cover, and allow to boil gently for approximately 15 minutes.
Whisk milk and cornmeal together; drain and rinse beans. Add to the pot along with the tomatoes (liquid included), corn, and cream. Stir until well blended and cook until heated through.
Top soup with diced avocado, and serve cubed mango on the side.