Rinse the rice under cold water until the water runs clear. Combine rice and water or broth in a medium saucepan, bring to a boil, then reduce heat to a simmer. Cook for 15-18 minutes, covered, then let sit for 5 minutes before fluffing.

Heat neutral oil in a large skillet over medium heat. Add ground beef and cook, breaking it up for about 5-7 minutes until browned. Stir in taco seasoning and water, simmer until thick and glazy for 3-5 minutes.

Assemble bowls: Start with a scoop of fluffy rice, add seasoned beef, and layer with black beans, corn, diced tomatoes, and shredded lettuce. Top with sour cream and cilantro.