Nutrition: per serving
Heat the oven to 220C/200C/gas 7. Scatter the squash in a large roasting tray and sprinkle over the paprika and 1 tbsp of oil. Season well with salt and pepper, then mix with your hands to coat. Roast for 30-40 mins or until golden and softened. Set aside to cool.
Put a large, deep frying pan on a medium heat. Drizzle in the remaining tbsp of oil then, once shimmering, cook the onion with a pinch of salt for 8-10 mins or until beginning to soften. Add the garlic, cumin and chard stalks, and cook for 10 mins, stirring regularly, until the stalks have softened.
Toss in the chard leaves, spice blend and harissa, then cook for 3-4 mins or until aromatic. Transfer the mixture to a bowl
and leave to cool.
Once cool, mix with the roasted squash and halloumi, and season to taste. Turn down the oven to 190C/170C fan/gas 5.
Brush three filo sheets with butter and layer them on top of each other. With the longest side facing you, arrange half of the filling in the centre of the rectangle then roll up to make a log. Transfer to a large lined baking tray. Repeat with three more filo sheets and remaining filling.
Connect the two logs to make a wreath. Tear the final filo sheet into four strips and weave them around the two logs. Brush all over with butter and scatter over the nigella seeds.
Combine the yogurt with the garlic, tahini, oil and lemon juice, and serve in the centre of the wreath.
