Dulce de Membrillo

Ingredients

• 1.5 kg ripe quinces (about 5)
• 1 lemon, juiced
• about 900 g granulated sugar, weighed at 80 percent of the pulp weight
• 1 vanilla pod, split lengthwise

Before you cook

• Rub the grey fuzz off each quince with a rough cloth under cold running water.
• Quarter the quinces without peeling or coring them, because the skin and pips carry the pectin.
• Squeeze the lemon and keep the juice to hand.
• Split the vanilla pod down its length with the tip of a knife.
• Line a 20 cm square tin with baking parchment, leaving an overhang on two sides.

Steps

1. Put the quince quarters in a large pan and pour in just enough cold water to cover them.
2. Bring to the boil over high heat, then drop the heat to a gentle simmer.
3. Cook for 35 to 45 minutes until a knife slides into the flesh with no resistance at all.
4. Drain the quinces and leave them until cool enough to handle, about 20 minutes.
5. Pull out the cores and pips and discard them, keeping the skins on the flesh.
6. Push the flesh through a food mill, or blend it to a smooth purée.
7. Weigh the purée and measure out 80 percent of that weight in granulated sugar.
8. Return the purée to the clean dry pan with the sugar, lemon juice and split vanilla pod.
9. Set the pan over low heat and stir until the sugar has completely dissolved.
10. Cook for 90 minutes to 2 hours over the lowest heat, stirring every few minutes with a long-handled wooden spoon.
11. Stand well back as the paste thickens, because it spits like lava.
12. Watch for the paste to turn deep ruby-amber and pull cleanly away from the sides of the pan.
13. Test it by standing the spoon upright in the centre, where it should stay put without keeling over.
14. Fish out the vanilla pod and scrape the hot paste into the lined tin.
15. Smooth the top with a wet palette knife and level it to about 3 cm deep.
16. Cool to room temperature, then chill uncovered for 12 hours until firm enough to slice cleanly.