In a large skillet, heat the olive oil over medium heat. Add the diced onion and cook until softened, about 3-4 minutes.
Add the minced garlic and cook for an additional 1 minute until fragrant.
Increase the heat to medium-high and add the ground beef. Cook until browned, breaking it apart with a spatula, about 5-7 minutes. Drain any excess fat.
Stir in the chili powder, cumin, paprika, salt, and black pepper. Cook for another 2 minutes to allow the spices to blend.
In serving bowls, layer the cooked rice, seasoned ground beef, black beans, corn, diced tomatoes, shredded lettuce, and cheddar cheese.
Top each bowl with a dollop of sour cream, sliced avocado, and fresh cilantro. Serve with lime wedges on the side.