Wildair in New York is a groundbreaking restaurant that has deeply influenced my cooking. It opened in 2015 as a sister to the now closed Contra, an impeccable fine-dining restaurant, and the same precision and ingenuity was applied to Wildair’s dishes, which have that perfect balance of elevated refinement and skilled execution, all combined with a casual playfulness. You can probably imagine my excitement, then, when I found out that one of my favourite dishes from one of my favourite restaurants also just happened to save waste by making an emulsion from the outer leaves of little gem lettuce cooked in butter. Pure genius.

Green “mayonnaise”’ with little gem salad

Only I would say this, but finding a use for the outer leaves of a lettuce has always niggled me. They’re nature’s plastic-free wrapping that protects the lettuce inside. Composting unwanted veg scraps is zero-waste 101, and a hugely powerful practice. Turning surplus food into fertile soil, rather than a waste product that ends up in landfill (where it may release methane, a greenhouse gas about 20-30 times more harmful than Co2), is a no-brainer, and something that many of us can easily do.

It’s quite radical, when you think about it: food rots and becomes the perfect soil to nourish further crops, thereby closing the loop and honouring the cycle of life. But, of course, we’re producing over 30% more food than we actually need, and using up precious and finite resources in the process. Reducing waste is worthwhile for that reason alone, not to mention the money it saves.

You can cook lettuce leaves like any leafy green (see my recipe for lettuce bag salad soup), but Wildair’s iconic recipe has a genius technique for using up the outer leaves. They’re wilted in butter, then turned into an emulsion, or “mayo”, by blending them with pistachios, which is then used to dress the rest of the lettuce for a salad. Even if you dress the salad liberally with the green mayonnaise, you’ll undoubtedly have some left over, but it keeps in the fridge for up three days and works on almost anything, from other salads to roast vegetables, grilled chicken or even drizzled over pasta or rice. I’ve adapted Wildair’s recipe a little so it works with any lettuce and nuts, and have also used a whole egg in the emulsion instead of just the yolk, to save having to find a use for the white.

Serves 2

For the green “mayonnaise” (makes about 200g, or enough for 4-6 servings) 100g butter 50g outer leaves from two little gems, or other lettuce, washed and dried thoroughly 20g shelled salted pistachios, or other nuts – white nuts such as pine nuts, cashews or blanched almonds will help keep the colour vivid, but anything works, really 1 small whole egg

For the salad 2 little gem lettuces, halved lengthways Extra-virgin olive oil, to taste Lemon juice, or white-wine vinegar, to taste 1 small handful fresh soft herbs (eg, chives, chervil, dill or parsley), leaves picked whole, stalks finely chopped)

First make the mayo. Melt the butter in a small saucepan, add the outer lettuce leaves, cover with a lid and cook for about a minute, stirring once or twice, until they’ve wilted. Tip into the jug of an immersion blender, add the pistachios and egg, then blend smooth; add more nuts, if need be, to give the mixture a mayonnaise-like thickness. Store in an airtight jar in the fridge for up to three days.

To build the salad, drizzle each little-gem half with olive oil and lemon juice, then season generously. Dress with a tight zigzag of the green mayo, then scatter over the herbs. Arrange on two plates and serve immediately.