Cut the cauliflowers, shallots, green beans and cucumbers into bite sized pieces then place into a large bowl, along with the sliced chilli (seeds removed) and toss with 50g of salt. Cover and place in the fridge overnight.
The next day drain the vegetables and rinse with cold water to remove the excess salt.
Place the vegetables in a large preserving pan with the vinegar, sugar, nutmeg and allspice. Add the crushed garlic and the salt. Bring to the boil, then turn down to simmer for about 5 minutes.
Take off the heat then drain the vegetables into a colander sat on top of a large bowl so you can retain the liquid.
Whisk together the cornflour, turmeric, ginger, curry powder, mustard powder and pepper. Add 100g of the reserved liquid and blend together to make a smooth sauce.
Pour the sauce into the preserving pan and with the heat on very low, slowly pour the rest of the reserved liquid into the sauce, whisking all the while.
Bring to the boil, then cook for 5 minutes until the sauce is smooth and thick.
Add the vegetables back into the sauce, stirring to coat thoroughly. Turn off the heat.
Decant into sterilised jars and store in a cool dark place until needed.