Quince paste

Halve and squeeze the lemon. Strain and measure out 15 ml of juice.

Wash and brush the fruit to remove the fuzz. Peel and carefully cut on a stable board. Remove cores, seeds and damaged parts. Weigh 1000 g net flesh, then cut into small pieces.

Put quince, sugar and lemon juice in a wide heavy-based saucepan. Stir and heat gently to dissolve the sugar in the fruit juices. Cook over low heat for about 75 minutes, stirring regularly and more often as it thickens, without letting it catch. The fruit should be very soft and the mixture thick, not runny.

Remove from the heat and carefully blend in the pan, keeping the blender head submerged to prevent splashes. The paste should briefly expose the base when pushed aside with a spoon. If it runs like apple sauce, return to low heat and stir to evaporate more moisture. Pour into shallow heatproof food containers and smooth.

Cool for about 1 hour in the shallow containers. Cover and refrigerate for 24 hours. Unmould once firm and cut into small portions. Keep refrigerated. This method does not produce a shelf-stable preserve.