Towel off  the downy fuzz of the quince.

Wash and quarter them.

Remove the skin and the seeds and cut each quarter in 2-3 slices.

Place the slices in a pot and add the water.

Gather the peels and the seeds, tie them into a cheesecloth and put it in the water.

Boil the quince until they are very tender. Take the pot off the heat and pass the content through a sieve, that you have placed inside another pot.

When they have strained thoroughly, squeeze the cheesecloth and discard the seeds and peels. Set the strained quince aside.

Pass the water where you have boiled the quince through a thin cheesecloth to so that it strains slowly.

Boil the liquid that you have collected until only 3/4 of it remain.

Add the sugar, stir so that it dissolves and boil over high heat so that it thickens. Add the lemon juice, the vanilla and after a few minutes empty in jars with a wide mouth and let it cool.