Method

1. Preheat the oven to 220C/gas 7. Heat a roasting tray in the oven for about 5 minutes. Pour in the oil and add the bones and trimmings in a single layer. Roast for about 30 minutes until they are golden and have the aroma that you get when you open your oven door to the scent of a wonderful roasted joint.

2. Remove the tray from the oven and use tongs to transfer the bones to a stockpot. Drain off most of the excess oil from the roasting tray, just leaving a tablespoon or so, and return it to the stovetop over a medium-high heat.

3. Add the chopped onion and whole garlic cloves to the roasting tray and fry until they are lightly coloured. Add the tomato paste and fry for a couple of minutes until it begins to darken. Add the white wine and stir well until it comes to a boil, then boil hard until the volume of liquid has reduced by half.

4. Pour the wine and onion mixture into the stockpot. Cover with water and bring to a boil. Skim the stock, then add the thyme and leave to simmer very gently for about 2 hours 30 minutes. Remove from the heat and leave to cool.

5. Strain the mixture through a colander, pressing down well with the back of a ladle to extract the maximum of liquid. Remove the fat either by skimming the surface of the stock immediately, or chilling the stock then scooping the fat off the top once it has solidified.

6. Return the stock to the boil and reduce to taste. Carefully strain through a fine sieve then store in the refrigerator for 3-4 days or the freezer for 3-4 months.