15 to 20 minutes. The simmering time of corn grits is usually 15 to 20 minutes, the flavor is soft and delicious, not sticky and not greasy, just right. If it is more than 20 minutes, the time is too long, the grits are easy to cook, the porridge with burnt flavor, affecting the taste, if it is less than 15 minutes, the time is too short, the grits are not cooked, the porridge is very hard, affecting digestion.