Oh, yummy! Quince jelly! I made it for the first time. First rub off the fur and wash the fruit. Then remove the stems and cores. Slice into pieces and cook on the stove in a pot of water until it is well cooked and mushy. Line a colander with cheesecloth, place it over a big pot, and dump in the mush. Let the mush drain overnight. Don't squish the mush or your jelly will be cloudy. Measure your juice, and add about 7/8 a cup of sugar for each cup of juice. Cook until it jells and can it!