Preheat the oven to 180ºC fan.
Line the bottom and sides of a 23 cm springform cake tin with baking parchment paper.

Put the cauliflower on a large, parchment lined baking tray and toss with the curry powder, half the oil and salt & pepper.

Roast for about 20 minutes, until cooked through. And lightly coloured. Set aside, and turn the oven temperature down to 170ºC fan.

Turn the heat down to medium and slowly add the milk a little at a time, whisking continuously to prevent any lumps, until incorporated and the sauce is smooth. Cook, whisking often for about 5 minutes until thickened slightly.

Off the heat, stir in cheese, garlic and mustard and 1/4 tsp of salt until cheese has melted.

Keep the filo sheets under a damp tea tower to prevent them from drying out. In a bowl, combine the melted butter and the remaining 1 1 1/2 tbsp of olive oil and keep to one side.

Working on sheet at a time brush the exposed side of the filo with the butter mixture and drape it into your prepared tin (buttered side up), pushing it down gently to fit. Continue in this way with the next filo sheet, brushing it with butter and then laying it over the bottom sheet, rotating it slightly so the overhang drapes over the sides at a different angle. Do this with all 7 sheets.

Spoon half the béchamel into the base and top with the roasted cauliflower florets. Spoon over the remaining béchamel, then crimp up the overhang so that it creates a messy “scrunched up” border around the edges. Leaving the centre of the pie exposed.

Brush the top of the filo border with the remaining butter mixture, then transfer the tin to a baking and bake for 30 minutes.

Using a tea towel to help you, carefully release the outer circle of the springform tin and return the pie to the oven for another 20 -25 minutes, or until the sides are nicely coloured and everything is golden and bubbling. Leave to settle for 15 minutes.

Top the pie with parsley and lemon zest and serve warm.

Enjoy.