In a large mixing bowl, combine ground beef, breadcrumbs, egg, chopped onion, garlic powder, salt, and black pepper. Mix gently until just combined.

Roll the mixture into 1½ inch meatballs, yielding around 16 meatballs.

Heat olive oil in a large skillet over medium heat. Add the meatballs and brown on all sides for 6-8 minutes.

Pour barbecue sauce into the skillet and simmer for about 5 minutes, turning occasionally.

In a blender, combine avocado, Greek yogurt, mayonnaise, chopped cilantro, lime juice, minced garlic, and water. Blend until smooth.

Divide cooked rice among four bowls and top with corn, black beans, red onion, avocado, and meatballs.

Drizzle avocado goddess sauce over each bowl and garnish with cilantro.