Heat oil in a medium skillet over medium heat and add rice. Stir until rice is slightly browned. Remove skillet from the heat and add the onions and fresh garlic, if using. Stir until onions are translucent. (The pan is usually warm enough to cook the onions and fresh garlic, keeping them from burning.)
Add water, chicken broth, if using, tomato sauce, bouillon cube, and garlic powder, if using. Stir and let mixture come to a boil; lower heat, cover, and simmer for 10 minutes. Stir gently after 10 minutes, cover, and let simmer for another 10 minutes. (If adding canned or frozen vegetables add them during the last 10 minutes.)
After the final 10 minutes of cooking, turn heat off, fluff rice with a fork and cover again for another 3 to 5 minutes so liquid can finish absorbing.
1 bouillon cube is the equivalent of 1 tablespoon of granulated bouillon.
You can use rice as a filling for a burrito bowl or a as a classic Mexican side dish.