To make the suya spice blend, place the nuts in a coffee or spice grinder and blitz in 1-second short bursts to a fine powder.
Transfer the nuts to a piece of muslin or a clean kitchen towel and squeeze out as much oil as possible, until you are left with a cookie dough-like texture. Tip into a bowl and break into fine crumbs using a fork.
Add all the spices and seasonings to the bowl with the peanuts and mix well. Store in an airtight container or glass jar away from direct sunlight for up to 3 months.
To make the spiced peanut puree, place a flameproof casserole over a medium heat and pour in the peanuts. Swirl the nuts around a few times, using a wooden spoon, to avoid burning. Roast until golden, then remove from the pan to cool.
Reserve 2 tablespoons (about 30g) of the roasted peanuts and place the rest in a food processor with the other puree ingredients. Add 60ml water and blend, scraping down the sides now and again. Add more water, a tablespoon at a time, to loosen the paste, if needed, until spreadable but with some texture. Season with ½ teaspoon fine sea salt and reserve 2 heaped tablespoons of the puree for later.
Preheat the oven to 200C fan/gas mark 7.
Carve a triangle into the stalk of the cauliflower and place it in the casserole. Spread the puree over the whole surface, covering it in a thick coating. Turn the cauliflower over, season the cavity and spoon some puree inside. Place the cauliflower bottom-side down and tuck the cherry tomatoes, red pepper and onion around the cauliflower. Brush or drizzle all the vegetables, including the cauliflower, with the oil and pour 60ml water around the sides. Cover with a lid and roast in the middle of the oven for 30 minutes, then remove the lid and roast for another 30 minutes, until beautifully dark and golden, and you can pierce a knife into the cauliflower with little resistance. Set aside while you prepare the sauce.
Place the roasted pepper, cherry tomatoes and onion in a food processor with the reserved peanut puree and blend until smooth. Drizzle with a little oil and season with a pinch of fine sea salt and black pepper.
Spoon the tomato and spiced peanut puree on to a warm serving plate and place the cauliflower on top. Chop the reserved roasted peanuts, scatter them over the top with the chopped coriander and sprinkle over the 1 teaspoon suya spice blend. Serve as a main dish or an accompaniment to your favourite salad, roast or grains.