It wasn’t until I started cooking for 2,000 or more people over a weekend at music festivals that I realised how the tops and tails of vegetables we lop off stack up. Often they don’t need to be removed at all, like the tails on carrots, beans and turnips, which look more attractive left on. When the soily tops do need to be removed, a little extra precision can save a lot of food.

One of my festival recipes is harissa. We used to cut the top off two kilos of chillies, wasting about 300g, until I realised you can just as swiftly pluck the green stalk off. Although preparing vegetables with care at home will save only a little food each meal, it will amount to a considerable size over a year.

If a recipe calls for the chilli seeds to be removed, don’t throw them away: dry them out on a plate with any other fleshy scraps to use as a spice to add heat to a dish later on.

The green stalks, however, can be put to a more magical purpose. They contain the beneficial bacteria lactobacillus, so you could start making a batch of your own yoghurt, from scratch and without a starter!

Homemade yoghurt

I can’t believe I’ve spent my whole life not making yoghurt. It is the easiest, most rewarding and fun thing to make – and so very delicious. The trick is to keep the yoghurt warm while it ferments. You could set the yoghurt in a flask or in a jar wrapped in tea towels.

Cook 20 min

Ferment 7 hr

Makes 1 pint

1 pint milk

10-15 saved chilli stalks, or 2 tbsp live yoghurt or yoghurt starter

Bring a pint of milk (preferably whole and unhomogenised) to a boil and simmer gently for one minute. Leave to cool until it is about 45-50C, or the temperature of a hot bath.

Drop in 10-15 saved green chilli stalks (or whisk in six tablespoons of live yoghurt or starter).

Pour into a flask or other container and put in a warm place, such as an airing cupboard. Leave it to ferment for seven hours, then refrigerate and eat within three to four weeks.