- Peel, core, and dice the quinces. Cook them till soft. Drain.
- Force the pulp through a sieve or purée in a blender. Weigh the purée.
- For every pound of purée measure 2½ cups of sugar. Cook the sugar with 2 cups water until it becomes a heavy syrup. As a test dip a wooden spoon into cold water, then dip it into the hot syrup; remove. If the sugar syrup on the spoon hardens and breaks, the syrup is ready.
- Put the fruit purée in the syrup and cook over low heat, or in a double boiler, while stirring constantly, until the paste is very thick, like a jam.
- Cook for a few more minutes. Pour into moistened molds. If you use the walnut halves, place them in the molds first and then pour the hot paste over them. Use small individual molds, or pour into a small baking pan and then cut the paste into diamond shapes to serve.
- This will keep for a long time in or out of the refrigerator if wrapped in foil or wax paper.
The texture should be like that of a Japanese soybean paste dessert, or like South American guava and other fruit pastes.