Sauté onion and garlic with the oil in a medium pot.
Add water and tomato sauce to the pot and cook on high until the water comes to a boil.
Add in the rice and reduce heat to medium-high until rice is simmering for about 20 seconds.
Add in the salt and stir the rice once around.
Turn heat down to low, cover, and simmer for about 35-40 minutes, or until cooked through. The water should be fully absorbed and the rice should still have a little bite and not be mushy.
Turn off the heat and let rice steam with the cover on for 10 more minutes.
Serve warm.