Thin porridge, also known as GRUEL or watergruel, is a type of thin porridge made from oats, barley, or other grains. It is usually cooked in water or milk and served as a breakfast cereal or as a light meal. GRUEL is a thinner version of porridge, while watergruel is a thinner version of GRUEL. Both are typically served with sugar, honey, or other sweeteners. Thin porridge is a popular dish in many cultures and is often served as a comfort food.