Heat your oven to 200°C/Fan 180°C/Gas 6. Slice off the end of the cauliflower stem and the outer leaves. Cut a cross through the bottom of the cauliflower stem.
Zest and juice the lime. Chop the marjoram leaves. Mix the lime zest and juice, yogurt, marjoram and some seasoning in a bowl. Spoon half the yogurt sauce into a serving bowl and set aside.
Pop the cauliflower in a large casserole dish. Spoon over the rest of the yogurt sauce. Cover with the lid or foil. Roast for 30 mins. Uncover. Roast for another 5 mins till golden.
Peel and roughly chop the onion. Halve the chilli. Scoop out the seeds and white bits. Finely chop the chilli. Peel and crush the garlic. Roughly chop the tomatoes.
Warm 1 tbsp oil in a pan. Add the onion. Fry over a medium heat for 5 mins till it starts to look glossy. Add the chilli, 1 ½ tsp cumin and the garlic. Stir and fry for 1 min.
Add the tomatoes and bulgar wheat to the pan with 200ml boiling water. Season. Cover and simmer over a low heat for 10 mins till all the liquid has been absorbed.
Roughly chop the parsley leaves. Take the bulgar wheat off the heat – it should be tender and not wet. Fluff it up with a fork. Stir in the parsley. Taste and adjust the seasoning if it needs it. Serve with the cauliflower and yogurt sauce.