How to make perfect pesto and why you're probably doing it wrong

Times

21-06-2025

Isn't it funny how it's always the simplest recipes that cause the biggest disagreements? Take pesto, for example. Typically it's made from five ingredients: basil, pine nuts, oil, garlic and cheese. Yet ask people in Liguria, the Italian region where the sauce originated, and you will be given a hundred different methods. Some add parmesan, others pecorino; some grind it by hand, others blitz it in a processor. In fact, the only things they agree on is that pre-made pesto in jars is an abomination (and don't even mention vegan pesto made with nutritional yeast) — and that the only basil worth using is Genoese, grown in fields cooled by sea breezes.
'If you haven't got good basil, make something else,' says Stevie Parle, the chef behind the popular Italian pasta restaurant Pastaio in central London. He waves a large bunch of Genoese basil under my nose and it's true, it does have a more robust, spicier, less sweet scent than the basil we are used to buying in the supermarkets, which has a more metallic, minty flavour. 'Basil really is the most important thing, and this has its own PDO [protected denomination of origin quality label], meaning it's come from the right region and has been grown in the right way, facing the coast so it doesn't get too hot or too cool.'
When you grow Genoese basil, you can pick a crop from it three times, but it's only the tender first crop that achieves PDO status. Parle buys his from Natoora, the vegetable wholesaler, and it comes with its roots intact to ensure freshness. 'I have tried repotting it and growing it in the past, but you will never get the same flavour because it's about the soil and climate where it comes from.'
That's the basil variety agreed on, but Parle warns me that you can go down a rabbit hole chasing an illusory concept of authenticity for almost every other detail. 'Even within Liguria there's a lot of variations, some of it regional, some of it between families. Some people will blanch their basil for 10 seconds before refreshing it in iced water, especially towards the end of the basil season when the leaves are bigger and tougher. Others will add a splash of milk or cream at the end.'
Parle's own quirk is to freeze the basil for 15 minutes before using it. 'It's something I overheard at my favourite restaurant to have pesto in — Da Laura, just up the coast from Portofino — and it makes absolute sense to me. It breaks the cell walls so you get a brighter, greener, more basily pesto.'
The other constituents are again a question of finding the best possible varieties. To this end, Parle prefers Italian or Middle Eastern pine nuts, which are longer than the more stubby and ubiquitous Chinese ones. Their flavour is much nuttier, something he enhances by toasting them briefly in a dry pan.
Then there is the choice of oil. 'This is getting quite niche now,' Parle admits, 'but you don't want a peppery oil from Tuscany as it will overpower the pesto. Ligurian oil is perfect, but it's quite hard to find in this country, so I'd recommend an oil from the south of France made from ripe black olives, which is more delicate, almost buttery.'
Your ingredients assembled, you have to decide whether to use a pestle and mortar, as is traditional, or a food processor. 'It's probably better if you do it with a pestle and mortar, and ten years ago when I used to write a recipe column, I'd have said you must,' Parle says. 'But it's just ridiculous. I've got three kids and two busy restaurants [recently he launched Town on Drury Lane] — I'm using a machine.'
Certainly not a knife, though. 'I actually watched a video this morning of a chef whom I really admire making his pesto with a knife, and I just thought, 'Mate, we need to have a conversation about this. I mean, why would you?' People would say you want a bit of texture, but I think that's rubbish. You want it to be completely smooth, as if you have spent hours grinding it by hand with your pestle and mortar.'
The final texture he controls by adding a little optional ricotta ('I like mine on the creamy side') or a splash of pasta cooking water to make it slightly looser and glossier.
You'd hope that would be all the controversies dealt with, but then we come to accompaniments. Pasta, obviously, but which one? 'I like lasagnetti,' Parle says, 'which are very fine, wide sheets, because I like the way the pesto sits on them. In Liguria you'll often get trofie, which are little twists, and they work well too. Spaghetti not so much, and I don't like conchiglie either because you don't want a shell full of pesto, you just want a slick covering.'
Parle also likes to add potatoes and green beans. 'I love a double carb,' he says. 'I cut my potato very, very thin on a mandolin, so it's as thin as the pasta, and then it takes the same amount of time to cook. It just adds another interesting texture and maybe also you're getting slightly starchier water, which I think is really important. And then a few green beans because they're delicious.'
That's pretty much where he draws the line. I suggest a smear of pesto on grilled fish, but he sticks his tongue out in disgust. 'No, it's not for fish, it's not for chicken — and please, it's not for sandwiches,' he says definitively.
Surely there must be something else, I ask. 'Oh OK, yes, soup. You can add a spoonful to a summer bowl of minestrone if you like. I'll concede that.'
Stevie Parle's ultimate pesto recipe
Parle freezes the basil for 15 minutes before using it
CHRIS MCANDREW FOR THE TIMES
Makes about 400ml
Ingredients
• 100g basil leaves
• 30g pine nuts
• 1 small garlic clove
• ½ tsp fine salt
• 90g ricotta (ideally fresh sheep's ricotta)
• 40g parmesan, finely grated
• 100ml extra virgin olive oil
Method
1. Wash and pick the basil, then lay the leaves flat on a tray and put in the freezer for 15 min — this locks in their colour.
2. Toast the pine nuts in a dry pan over a medium heat for 2-3 min, until golden and fragrant, then leave to cool.
3. Crush the garlic with the salt until smooth, using a pestle and mortar or the flat side of a knife.
4. In a high-powered blender, mix the basil, pine nuts, garlic paste, ricotta, parmesan and olive oil until it becomes silky and bright green.
5. Taste and adjust with seasoning. Loosen with a splash of cold water or more oil if needed.
Six alternative pesto combinations
Pesto alla Trapanese
GETTY
• Pesto alla Trapanese — a Sicilian version with almonds instead of pine nuts combined with fresh chopped cherry tomatoes, basil and pecorino.
• Pistachio — use pistachios instead of pine nuts, and leave out the ricotta for a richer, silkier texture.
• Rocket and walnut — use peppery rocket and toasted walnuts instead of basil and pine nuts to make a punchier, more wintery version.
• Courgette and mint — either add mint alongside the basil or replace it, depending on your taste. Blend raw courgette, mint, garlic and lemon zest with a little parmesan for a light, summery twist.
• Wild garlic — swap basil for wild garlic leaves in spring for a much stronger and earthy flavour profile. Keep everything else the same.
• Parsley and hazelnut — swap out the basil for flat leaf parsley and the pine nuts for toasted hazelnuts. The toasted nuts give an almost woody, rich taste.