In a mixing bowl, combine ground beef (or turkey), breadcrumbs, egg, chili powder, cumin, garlic powder, onion powder, salt, and black pepper. Mix well until all ingredients are fully incorporated.
Form the mixture into small meatballs, about 1 inch in diameter.
Heat olive oil in a large pot or Dutch oven over medium heat. Add the chopped onion and bell pepper, sautéing for about 5 minutes until softened.
Carefully add the meatballs to the pot and cook for about 5 minutes, turning occasionally until browned on all sides.
Pour in the beef broth, diced tomatoes, black beans, and corn. Stir to combine and bring to a simmer.
Allow the soup to simmer for 15 minutes, letting the flavors meld together and the meatballs cook through.
Taste and adjust seasoning if necessary.
Serve hot, garnished with fresh cilantro and lime wedges on the side.