Cored and cut the quince into cubes, leaving the peel on.
Add just enough water to cover the quince cubes in a deep saucepan. Bring to a boil, and let simmer for 20 minutes or until the quinces are soft.
Drain off excess water and put the mixture through a food mill or handheld blender, blending it into a soft, smooth consistency.
Add as much white sugar as possible, or a mix of white and brown, to the quince purée. This requires weighing or a good eyeball estimation. You want an equal amount of sugar by weight to the quince purée.
Reheat this mixture to a simmer for 30 minutes, stirring constantly to prevent it from burning on the bottom.
Add 1/2 vanilla bean, the juice of 1 lemon and lemon zest, crushed seeds of 2 cardamom pods, a cinnamon stick and/or 1 clove. Heat until the mixture thickens and turns slightly red in colour. (Note: Some quince varieties remain yellow.)
Remove the vanilla bean and cinnamon stick.
Scoop the mixture into a shallow square Pyrex or a 2-inch shallow plate lined with parchment paper. Cover with parchment paper and set aside in a cool place for a few days, not in the fridge, as it won’t set up properly. It will harden a bit and should be a bit softer than gummy bear consistency but firmer than jello when ready.
Cut into cubes or slices to serve.