Beetroot Ketchup with chilli

Preheat your oven to 200C/400F/Gas Mark 6.
Place the beetroot (whole and un-peeled) in a large piece of foil, drizzle with a little oil, wrap up to enclose them and place on a baking tray in the oven for an hour.
After the hour is up, test each one with a sharp knife - if it passes through easily, the beetroot is cooked so remove it. Return any which aren't cooked to the oven and keep testing every 10 minutes until they are all tender.
When they are cool enough to handle, trim and peel the beetroots.

Chop the beetroot into small-ish pieces.
In a large saucepan, heat the sunflower/rapeseed oil. Peel and finely chop the onion and carrot, and add to the pan. Finely chop the celery, peel and crush the garlic and add to the pan. Stir through the cumin, and cook gently for 5 minutes until softened.
Whilst it is cooking, finely chop the chilli - leave the seeds in for a spicier ketchup or take them out for a milder flavour.
Add the beetroot, chilli, salt and red wine vinegar to the pan, and simmer gently for 20 minutes.
Remove from the heat, and leave to cool for a few minutes. Spoon the beetroot mixture into a blender or food processor.
Blitz on the highest possible speed for 2-3 minutes until completely smooth. (For a super-smooth ketchup you can pass it through a fine sieve at this point).
Return the ketchup to the pan, then add the sugar, bring to the boil, and lower to a very gentle heat.
The consistency of your ketchup at this point will depend on the water content of your beetroot. If it is too thick, add a little water until it is a glossy, pourable sauce. If it is too runny, keep it simmering over a gentle heat until it has thickened. You can't over-cook this ketchup so just keep adjusting until it is exactly as you want it.
When it has cooled slightly, pour into warm, sterilised bottles or jars. (A funnel will make this process much less messy!).
The ketchup will keep, (ideally in a cool, dark place), for 3 months, and once opened, in the fridge for 2 weeks.