One-third of Americans live at altitudes above 3,000 feet, where cooking can be a bit more challenging. The higher you go, the drier and thinner the air becomes, so moisture evaporates more readily and water boils at a lower temperature. To prepare rice successfully, you may need to increase both the volume of water and the cooking time.
Follow the standard ratio of 2 cups of water for each 1 cup of dry long-grain white rice when cooking at altitudes between 3,000 and 5,000 feet. Increase the water by 2 tablespoons to 1/4 cup for altitudes above 5,000 feet, adjusting the amount upward as you go up in altitude.
Cook long-grain white rice for 15 to 20 minutes at altitudes up to 5,000 feet; increase the time incrementally as the altitude increases. Expect rice cooked above 5,000 feet to take 25 minutes or more.
Adjust as needed, adding more water if it evaporates too quickly and letting the rice cook longer if the kernels seem underdone.
Cook rice in a pot with a glass lid so you can monitor its progress without lifting the lid.
Some varieties of rice, such as brown or arborio, require more liquid and a longer cooking time than standard long-grain white rice, even at sea level.
Don't turn up the heat in an effort to speed up the cooking. Rice must be simmered at a low temperature for the kernels to absorb the water.