Preheat the oven to 400 degrees. Line a baking sheet with parchment paper.
Place the ground meat, rice, garlic, egg, cumin, oregano, cilantro, salt, and pepper in a large bowl and mix gently until just combined. Do not overmix.
Using wet hands, roll the mixture into 1-inch balls and place onto the prepared baking sheet. Bake for 20 minutes, until cooked through and lightly browned. Set aside.
Meanwhile, heat the oil in a large pot over medium-high heat. Add the onion and cook for 5 minutes, until soft and translucent. Add the carrots, zucchini, cumin, chili powder, oregano, salt and pepper and cook for 8-10 minutes, stirring often.
Add the stock, tomatoes, and bring to a boil then reduce heat to a simmer for 10 minutes.
Add the meatballs, black beans, and corn to the pot. Simmer for an additional 5-10 minutes or until the corn is tender.
Adjust seasonings and ladle into bowls and serve with optional toppings.
Recipe by Three Hungry Boys at https://www.threehungryboys.com/2021/04/12/mexican-meatball-soyp/