Cook the rice according to package instructions. Once cooked, let it rest for a few minutes, then fluff with a fork to separate the grains. Set aside and keep warm.
Heat olive oil in a large pan over medium heat. Add the ground beef and cook while breaking it apart into small pieces. Continue cooking until the beef is fully browned and no pink remains.
Drain excess grease if needed. Sprinkle taco seasoning evenly over the beef. Add water and stir well to combine. Let the mixture simmer for 5 to 7 minutes, stirring occasionally, until the sauce thickens and coats the meat.
Add black beans and corn to the pan. Stir gently to combine with the seasoned beef. Cook for another 2 to 3 minutes until everything is heated through. Taste and adjust seasoning if needed.
Prepare toppings by chopping lettuce, dicing tomatoes, and shredding cheese if needed. Keep all toppings ready for assembly.
To assemble, add a scoop of warm rice into each bowl. Spoon the beef, bean, and corn mixture over the rice.
Top each bowl with lettuce, tomatoes, and shredded cheese. Add a dollop of sour cream and a spoonful of salsa on top.
Serve immediately while warm. Mix everything together before eating for the best flavor in every bite.