Preheat oven to 350 degrees Fahrenheit.
In a large skillet over medium heat, cook ground beef and chopped onion for 6 to 7 minutes until beef is browned and onion is soft.
Drain excess fat from the skillet.
Stir in black beans, diced tomatoes with green chilies, chili powder, cumin, garlic powder, salt, and black pepper. Simmer for 5 minutes.
In a mixing bowl, whisk together cornmeal, milk, and egg until smooth.
Grease a 9 by 13 inch baking dish.
Pour half of the cornmeal batter into the prepared dish and spread evenly.
Spoon the beef mixture over the cornmeal layer, distributing evenly.
Pour the remaining cornmeal batter over the beef layer and spread gently.
Sprinkle shredded cheddar cheese and sliced black olives over the top.
Bake for 30 to 35 minutes until the topping is golden brown and set.
Let rest for 10 minutes before slicing.
Garnish with chopped fresh cilantro before serving.
