Cut the lemon in half and mix the juice of one half in 2 liters of cold water.
Peel the quince and cut in large cubes discarding the core.
Place the cut quince in a pot with lemon water, ensure all pieces are submerged to keep them from discoloring
Add the cinnamon sticks and cook at medium temperature for about 25 minutes until the quince is soft.
Once cooked, add to a food blender to make a fine puree. Pour the puree into a large pan and place back on the stove.
Add sugar and juice from the left over lemon and reduce the puree on medium heat while stirring for about 12 to 15 minutes.
The puree should now be sticky with a caramel like consistency.
Transfer the puree in small containers to chill or for next day usage, pour the puree into one large container, if you prefer one slab of quince puree.