Basil pesto

Pound the garlic, kosher salt and pine nuts in a mortar to a smooth paste; the smoother it is, the better the sauce emulsifies.

Rinse, dry and stem the basil, weigh out the same weight as the pine nuts, and pound to a chunky paste.

Add a splash of olive oil and the grated parmesan, then work in the rest of the oil in splashes to a textured but smooth, almost creamy pesto.

If the pesto breaks or goes oily, blitz it in a blender or food processor with a tablespoon of hot water.

To store, pour a thin layer of olive oil over the top to seal it from air; it keeps four to five days, or one to two weeks sealed or with blanched basil.

To keep the colour, drop the basil into boiling water about five seconds until it wilts, then straight into ice water, and dry it on paper towels.

In a food processor instead, blitz the pine nuts, garlic and salt about 30 seconds to a rough paste, add the basil, grate in the cheese, then drizzle the oil down the feed spout with the machine running until it becomes a sauce.

Variation, sun-dried tomato pesto: 30 grams of unsalted almonds, one clove of garlic and one teaspoon of kosher salt blitzed to an almond sand, then about one cup of rinsed and dried sun-dried tomatoes, a couple of loose basil leaves, parmesan and all the oil at once.

Variation, kale and walnut pesto: 30 grams of blanched kale, 30 grams of walnuts, double the garlic, parmesan and romano, and a quarter to half a cup of olive oil; parsley or tarragon can go in too.

Variation, carrot top pesto: carrot tops with pepitas and cotija cheese; no amounts stated.

Variation: pistachios, garlic, blanched and shocked sugar snap peas, fresh mint and ricotta salata, adjusted with salt, pepper and lemon zest; no amounts stated.

Cook the pasta, reserve at least half a cup of the starchy water, drain and return the pasta to the hot pan off the heat.

Add the pesto and about a quarter cup of pasta water and agitate hard to emulsify into a creamy sauce.

Finish with two tablespoons of butter per pound of pasta.