Quince paste is a thick jam made from the fruit of the quince tree. This richly red to orange-colored jam has a sweet taste and a slightly floral flavor, and it is extremely popular in Southern Europe and the Middle East.ou need 3 quince, juice of ½ lemons, 2 cups sugar, and a pinch of salt. Peel and core your quince and cut into wedges. Put the quince in a boiler and cover with water. Add the lemon juice. Bring to a boil, until the fruit is very soft.