Gem lettuce with fridge-raid dressing

This dressing came about when I had a load of herbs in the fridge that needed using up. Don’t be too precious about the weight of individual herbs: so long as the total net weight is about the same, you’ll be fine. It’s worth making extra, because it keeps for a day in the fridge and is lovely spooned over all sorts of things, from chicken salad and tuna niçoise to roast root vegetables and tomato and feta salad. Serves four as a side dish.

½ very ripe avocado, flesh scooped out (90 g net weight)
1 1/2-inch (4 cm) piece ginger, peeled and roughly chopped (20 g net weight)
1 small garlic clove, peeled and crushed
2 lemons: finely grate the zest of 1 to get 1 tsp, then juice both to get 3 tbsp (please, start to juice first lemon. If you feel you dressing needs more acidity, please juice another lemon)
1 green chilli, roughly chopped (deseeded if you don’t like much heat)
1 tbsp tahini
85 ml (5 tablespoons + 2 teaspoons) olive oil
Salt to taste
1/2 cup (10 g) basil leaves (I used mint leaves)
1/2 cup (10 g) tarragon leaves (I used 1/4 cup)
1/2 cup (10 g) dill (I used 1/4 cup)
1/2 cup (10 g) parsley leaves
1/2 cup (10 g) 10g cilantro leaves
4 gem lettuces, trimmed and cut lengthways into eighths (I used a regular lettuce)
2 tsp black sesame seeds, lightly toasted

Put the avocado, ginger, garlic, lemon zest and juice, chilli, tahini and five tablespoons of oil in the small bowl of a food processor. Add a third of a teaspoon of salt, blitz to a smooth paste, then add the herbs. Blitz again and, with the motor running, slowly add 60 ml water until smooth.

Mix the lettuce with two teaspoons of oil and an eighth of a teaspoon of salt, then transfer to a platter. Spoon over the dressing, scatter on the sesame seeds and serve at once.

Recipe comes from "Simple" by Yotam Ottolenghi.