1

Preheat the oven to 200°C, fan 180°C, gas mark 6. Meanwhile, mist a small pan with cooking spray, put over a medium heat and add the onion. Cook for 8-10 minutes, until just softened, then set aside to cool.

2

Spread the carrot, parsnip and butternut squash chips onto a large tray and mist with cooking spray. Season to taste and roast for 45 minutes, turning halfway through, until golden brown all over and cooked through.

3

Put the beetroot in a food processor and blitz until broken into small pieces, then add the black beans and pulse again to a rough purée. Transfer the mixture to a bowl and add the onion, beaten egg, breadcrumbs, paprika and cumin. Season to taste and mix well, then form the mixture into 4 patties.

4

Mist a non-stick pan with cooking spray and cook the burgers for 4-5 minutes on each side, then transfer to a roasting tray and cook in the oven for the final 20 minutes of the vegetable roasting time.

5

Mix the Greek yogurt with the ras el hanout. Serve the burgers in the buns with the lettuce leaves, a spoonful of the yogurt, and the vegetable chips on the side.