Bagged salad is one of the most wasted foods in Britain, with over half of it ending up in landfill. I have had this recipe in mind since my first cookbook, A Girl Called Jack, and although it is something I make for myself on a regular basis, absorbed into my household as a common staple, it has never been committed to paper (nor screen) until now. Bags of salad can be expensive to buy full price, but can often be found in the reduced chiller at the supermarket, which is where I nabbed the first one I ever made this with. (I have priced it as a regular bag of salad to hold off the stampede to my local cornershop supermarket; it’s a long way to come for a half price half wilted bag of leaves!) I like using salad leaves for pesto for variety, too, the peppery tang of rocket, the pop of colour from a beetroot leaf or baby chard, the sweet crunch of a tiny piece of spinach – and as an easy way towards five a day, hot and slathered all over slick soft pasta. May the reduced stickers be ever in your favour.

Serves 6 at 13p each. This post is not sponsored; I provide links to the ingredients that I use so you can see how I calculate my recipe costs, and I may earn a small commission if you click the links or purchase any ingredients. All prices correct at the time of printing and are subject to change.

150g bag of salad, 62p

1 fat clove of garlic or 1/2 tsp garlic paste, 2p (69p/4 bulbs)

60ml sunflower oil, 7p (£1.10/1l))

20ml lemon juice, 4p (39p/250ml)

a pinch of salt, <1p

a pinch of pepper, <1p (43p/jar)

Finely chop your salad into smithereens with a heavy, sharp knife. If you have a bullet blender or food processor you may find it easier to bung them all in here, but (on a good hands day) I enjoy the vigorous satisfaction of grinding a blade repeatedly into a bunch of leaves until they resemble a small pile of dust.

Pop the tiny pieces of leaf into a bowl. Peel and finely chop your garlic, if using fresh cloves, and add that too, or a teaspoon of garlic paste. (I have been making my own garlic paste by the truckload to use in times of seized-up fingers, and I will write about it shortly).

Add the oil, lemon juice, salt and pepper and mix well. Store in a jar in the fridge for up to 4 days, or in the freezer for a few months.

You may want to add finely grated cheese to it to make something more closely resembling a traditional pesto, which would be a marvellous addition. I served mine warm over spaghetti with a couple of very finely chopped tomatoes folded through and a smattering of extra pepper.

All text and photography copyright Jack Monroe.

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