Cook the rice according to the package directions.
In a large pot, brown the ground beef over medium high heat.
Transfer all but about a tablespoon of grease to a paper towel lined bowl to drain the grease from meat.
In the same pot with a bit of grease left, reduce the heat to medium, and sauté the onion until translucent.
Add the ground beef back in the pot. While stirring, add all the spices for Homemade Taco Seasoning (chili powder, garlic powder, onion powder, oregano, paprika, cumin and beef bouillon) OR a packet of the pre-mixed taco seasoning.
Add corn starch, water and tomato sauce. Stir well. Bring the meat sauce to a boil over medium heat. Then cover and reduce the heat to LOW. Simmer about 15 minutes or until the bouillon is completely dissolved.
Serve over rice. Top with lettuce, cheese and tomatoes. Add sour cream, salsa and/or hot sauce as desired.