Question: how much water to cook 1 cup red lentils?
Answer: Cook on a stovetop, using 3 cups of liquid (water, stock, etc) to 1 cup of dry lentils. Be sure to use a large enough saucepan as the lentils will double or triple in size. Bring to a boil, cover tightly, reduce heat and simmer until they are tender. For whole lentils, cook time is typically 15-20 minutes.