In a large soup pot or Dutch oven, cook the ground beef, onions, and garlic over medium-high heat until browned. Be sure to crumble the beef as it cooks to ensure even cooking. Drain any excess fat for a lighter soup.
Stir in the taco seasoning until well combined, allowing the spices to infuse into the meat.
Add the beef stock, corn, black beans, diced tomatoes, tomato purée, lime juice, salt, and uncooked rice to the pot. This combination creates a hearty and colorful soup.
Bring the mixture to a boil, then reduce the heat, cover, and simmer for 20-25 minutes, or until the rice is tender. Stir occasionally to prevent sticking.
Stir in the fresh cilantro just before serving to maintain its vibrant flavor.
Serve the soup hot, accompanied by cheese, sour cream, lime wedges, extra cilantro, and tortilla chips on the side for added texture and flavor.
Notes
For a spicier kick, add a dash of hot sauce or diced jalapeños to the soup.