What Is Pistou?

Garlic - a crucial ingredient in French pistou sauce

Short answer
Pistou shares many similarities to pesto, although it omits the creamy pine nuts, contains a little less basil, and ramps up the garlic for a robust garlicky kick.

Long answer
Pesto Genovese, the classic Italian sauce we all know and love, contains just seven ingredients: basil, olive oil, pine nuts, garlic, salt, pecorino, and parmesan.

Pistou bears certain similarities, but the oldest pistou recipes are dramatically simplified versions and call for nothing more than basil, oil, garlic, and salt.

Nowadays you will often find the inclusion of Parmesan (or occasionally a more quintessentially French cheese like Gruyère). Some brave cooks even dare to include controversial ingredients such as parsley, tomatoes, lemon juice, and pepper.

Can you handle the garlic?
Being the garlic-snowflakes that we are, we can't handle the number of raw garlic cloves recommended by chefs such as Raymond Blanc. Rather than cut back on the amount of garlic, though, our compromise is to simply roast the garlic first. You still get a generous, garlicky smack around the chops, but it won't have the same spicy, lingering characteristics as its raw counterpart. If you find you've been too heavy-handed, then there are some ways to fix garlicky pesto. They are far from perfect, but they should at least save your pistou from the bin.

A potted history of pistou vs pesto
Translating as "pounded," pistou can be traced to the region of Provence, where it is most famously used in the wonderfully rustic Provençal dish, soupe au pistou. This minestrone-style soup, commonly made with beans, onions, tomatoes, carrots, and vermicelli, is famously finished off with a generous dollop of herby pistou just before serving.

In exactly the same way that the traditional basil pesto recipe was tweaked by the Sicilians to incorporate their beloved tomatoes, different regions of France have their own preferences for what cheese to use in their pistou. We applaud the Niçoise for using the wonderfully nutty Gruyère, while in Marseille you may find chefs using the semi-soft cheese from Lille, Mimolette.

Food processors are strictly forbidden when making pistou
Despite the differences between pistou and pesto, there's one thing that everyone can agree on: they must be made in a pestle and mortar. A food processor simply slices ingredients thinner and thinner, whereas doing it by hand crushes the ingredients, resulting in more flavour release.