This is now my favourite way to cook cauliflower from Ottolenghi and is a perfect side for a never ending list of dishes.
✔️1 large cauliflower
✔️45g unsalted butter, softened to room temperature
✔️2 tbsp olive oil
✔️1 lemon, cut in to wedges to serve
✔️flaked sea salt
Using a pair of scissors, lightly trim the leaves at the top of the cauliflower, so that about 5cm of the actual cauliflower head as exposed.
Fill a pan (which is large enough to fit the cauliflower in) 3/4 full of salted water. Bring to the boil, then carefully lower in the cauliflower, exposed head down. Return to a boil, cook for six minutes, then use a slotted spoon to transfer the cauliflower into a colander, exposed head down. Set aside for 10 minutes, to drain and cool.
Pre-heat the oven to 170° fan.
Mix together the butter and oil. Place the cauliflower in a medium baking tray, exposed head now facing upwards, and spread the butter – oil mix all over the flower, followed by 1 1/4 teaspoons of flaked salt. Put in the oven and roast for 1 1/2–2 hours, basting the cauliflower with the oil five or six times during cooking, until the cauliflower is really tender and dark golden – brown and the leaves are crisp and charred.
Remove from the oven and set aside for five minutes before serving.