Remove the label from the can. Fill a large pot with enough water to cover the can by 1-2 inches. Bring to a boil and simmer for 2 1/2 - 3 hours. Check water level every 30 minutes and add more water as needed, keeping can covered throught the entire cooking process. Remove pan from heat (leave can in water) and let dulce de leche come to room temeperature. Will keep 7-10 days. Enjoy!!!