To make the puree, place the clementines in a saucepan of water and bring to a boil, and then simmer for 20 minutes. Drain the water out and cover the clementines with fresh water. This helps to get rid of some
of the bitterness. Bring the water to a boil and then simmer again for 30 minutes, or until the clementines have softened and are squishy to the touch.