Step 1

Heat the oil or butter gently in a large saucepan, then add the base ingredients, the aromatics and the main ingredients. Stir around to coat everything in the fat, then sweat very gently for 10-15 minutes.

Step 2

Add 1litre/1¾pints of stock or other liquid, saving the rest for thinning down (if necessary), and season with salt and freshly ground black pepper. Bring up to the boil, then simmer gently for about 20 minutes until all the vegetables are tender.

Step 3

Liquidise in several batches, and return to the pan. Thin down with the reserved stock, water or milk as required, and check the seasoning

Step 4

Reheat when needed.