Ventilate your kitchen well. Place a large frying pan on a high heat and, once very hot, add the garlic and cook for 3 minutes, or until charred on the outside. Transfer to a chopping board and roughly chop. To the same pan, still on a high heat, add the chillies and toast until fragrant, about a minute, then transfer to a heatproof bowl. Pour enough boiling water over the chillies to cover and weigh them down with a small plate. Leave for 30 minutes, to soften and rehydrate, then strain through a sieve (saving the chilli water for another use). Set the pan aside to cool slightly.

Return the pan to a medium-high heat, add the crushed cumin, coriander and caraway seeds, the Kashmiri chilli, tomato paste and 2 tablespoons of the oil and cook, stirring all the while, for 2–3 minutes, until fragrant and deeply red. Transfer the mixture to a food processor along with the salt, sugar, rose petals, chopped garlic, rehydrated chillies, lemon juice, vinegar, rose water and 2 tablespoons of the oil, and pulse until you have a coarse paste, scraping down the sides of the bowl a couple of times throughout. Stir in the remaining 4 tablespoons of oil.

Transfer the mixture to a sterilised jar and refrigerate if not using right away. Top the harissa with more oil to seal (this’ll help it keep for longer).

Keep in a sealed, sterilised jar in the fridge for up to 2 months. Keep the mixture sealed with olive oil and use a clean spoon every time you dip into it. – Use in place of storebought ‘rose harissa’ for any recipe in the history of Ottolenghi books!