The quinces are washed well with down, peeled and cut, the box with seeds and the woody part is removed, then small cubes are cut.
In a saucepan with a thick bottom put the sugar and water to boil then add the chopped quinces.
Boil for 30-35 minutes, add the juice of half a lemon and leave on low heat for about 15 minutes until the syrup thickens and the jam is bound.
Do not boil more than necessary! This way you will get a jam with a beautiful color.
Put the vanilla and chopped walnuts, mix lightly then pour the jam into washed and dried jars well.
Staple the jars and turn them upside down and leave to cool until the next day wrapped in beds or in the oven of the stove heated to 100 degrees.