Place the cashew nuts, chutney, saffron (or turmeric) and boiled water in a jug and leave to soak.
Preheat the oven to grill setting (or as high as it can go).
Place the cauliflower in a large mixing bowl. Mix the yoghurt, paprika, lemon zest and chutney together in a small bowl, then combine the marinade with the cauliflower florets, spreading it well over each floret.
Place the marinated cauliflower on a large prepared baking tray and season with salt and black pepper. Place the tray in the center of the oven and roast for 12 - 15 minutes, until the florets are browned around the edges.
Add the oil and onion to a large non-stick skillet, and fry on medium heat until translucent. Add water as needed to prevent sticking.
Add the garlic, ginger, cinnamon, cardamom and cloves to the onions and fry for 1 minute, then turn off the heat. Add the tomato paste and a splash of boiled water, then transfer this mixture to a blender and blend until it is super smooth, then return it to the skillet. Turn the heat on low and cook for another 5 minutes, stirring regularly.
While the onion mixture is cooking, blend the cashew nut mixture until super smooth, then add it to the onion mixture in the skillet.
Add the tofu and then cook for another 5 minutes on medium heat until the sauce begins to thicken slightly. Turn off the heat and add the cauliflower.
Gently mix the cauliflower into the sauce. Be careful not to break up the tofu.
Taste the sauce and season with salt and black pepper as needed.
Next, pour the sauce into an oven-proof casserole dish and put it under the grill until golden and bubbling.
Garnish with fresh herbs and serve with steamed rice and a big green salad.