Ingredients

Step by step

1. Finely slice the fresh mushrooms, then chop into small pieces. Put in a very large bowl, sprinkle over the salt, then stir together to distribute it evenly. Cover and leave for about 24 hours at room temperature.
2. The next day, put the dried porcini in a small heatproof bowl, cover with 200ml boiling water and leave to soak. When soft, roughly snip the mushrooms with scissors, but leave them in their soaking liquor.
3. Now drain off the liquid from the salted mushrooms (they will have shrunk significantly). Cover them with cold water and swirl around, then drain again in a colander, but don’t squeeze out the liquid.
4. Put the rinsed salted mushrooms in a large pan with the soaked porcini mushrooms and their liquor, the onion and all the spices. Add the sugar and vinegar and bring to the boil, then reduce the heat and simmer for 30 minutes. Don’t worry that it doesn’t look like a lot of liquid, though if it looks too dry during cooking you can add a splash of water. After 30 minutes, stir in the sherry and bubble for 1 minute, then remove the pan from the heat.
5. Line a colander or large sieve with clean muslin and place over a bowl. Tip in the mushroom mixture and leave to drain. When cool enough to handle, gather up the corners of the muslin and squeeze out the remaining juice – the mushrooms will be holding far more liquid than you think.
6. Pour the liquid into hot, sterilised bottles and flip the lids over the top of each, but don’t press down to seal yet. The ketchup must now be sterilised Sterilising and sealing Wash jars and bottles with very hot soapy water, then rinse and place in a warm oven (160°C, fan 140°C, gas 3) for 10 minutes. Always fill jars to the brim, then cover either with sterilised twist lids, or with waxed discs and cellophane covers. Label when cold. Store in a cool dark place (or as directed in the recipe). 7 to prevent fermentation (because of its relatively low acidity level). Place 3 sheets of kitchen paper in the bottom of a deep pan, then add the bottles, making sure they do not touch each other or the pan sides.
7. Add enough hot water to come up to the neck of the bottles (just above the level of the ketchup), then cover the pan with a lid (made of foil, if necessary). Bring up to the boil then simmer for 30 minutes. Now seal the bottles and leave in the water until they are cool enough to remove. Store in the fridge when fully cooled.
   Tip

   Sterilising and sealing: Wash jars and bottles with very hot soapy water, then rinse and place in a warm oven (160°C, fan 140°C, gas 3) for 10 minutes. Always fill jars to the brim, then cover either with sterilised twist lids, or with waxed discs and cellophane covers. Label when cold. Store in a cool dark place (or as directed in the recipe).