Heat the butter in a wide saucepan over a medium heat. Sizzle the onion, carrots, bay leaves and thyme in the pan for 15 mins until the veg starts to brown. Scatter over the sugar and continue to cook for a further few minutes until sticky and caramelised. Stir in the flour until sandy. Cook for 1 min, then add the yeast extract, tomato purée, vinegar and soy sauce to make a sticky paste. Pour over the madeira and bubble for 1 min.

Add the stock, then crush the veg with a potato masher. Bubble everything together for 10 mins until you have a thickened sauce that just coats the back of a spoon. Sieve and use straightaway as a veggie gravy or as the base to a turkey gravy. Can be cooled, then frozen for up to three months.