Rinse off the quince and then peel them. Cut them in quarters and remove the seeds. Then cut lengthwise in small pieces, put them in a bowl, covered with cold water and add the lemon juice. This way we avoid discoloration, while cutting them into pieces.
Drain the quince, put them in a pot and sprinkle with the sugar. Pour in the water, 2-3 drops of lemon juice and boil until the quince are tender and the syrup has thickened.
Remove the pot from the heat and let the preserve cool down overnight.
The following day, we put the "gliko tou koutaliou kidoni" into sterilized airtight glass jars and keep it in the fridge.