In a medium saucepan over medium heat, warm the oil. Add the onion and cook for about 5 minutes, stirring occasionally to avoid browning. Add the chile powder. Cook for about 1 minute, stirring occasionally. Add the rice. Stir to evenly coat the grains of rice with oil. Add the remaining ingredients, including 3 cups of cold water. Stir. Bring the mixture to a simmer. Reduce the heat to low, cover the saucepan with a tight-fitting lid, and cook until the rice is tender and has absorbed all the water, 18 to 20 minutes. Remove the saucepan from the heat and leave it alone for 5 minutes. Remove the lid and fluff the rice with a fork. Serve warm.