Mix all the marinade ingredients together in a bowl, season well with salt and pepper and add the prawns. Mix well to coat in the marinade and set aside in a cool place until ready to cook.
Soak the wooden skewers in water, this will stop them from burning during cooking.
Next heat up a medium, heavy-based saucepan. Add the oil and butter, when melted throw in the onions and allow them to sizzle gently for 2 minutes. Add the garlic and cook for 1 minute, stir well.
Now it’s time to add the cooked root vegetables, stir gently as you don’t want the chunks to break up too much. Season with pepper sauce, turmeric, thyme and stir well. Sprinkle over a hefty pinch of both salt and pepper too.
Add the coconut milk and nutmeg, stir gently again and bring to the boil. Turn the heat down to a low heat and place a lid on the pan and cook gently for around 20 minutes.
Meanwhile heat a griddle pan to high and skewer the prawns onto the wooden skewers (4 on each skewer). Place prawns onto the griddle and cook for 2 minutes on each side. Drizzle the remaining marinade over the prawns as they are cooking.
Remove the lid from the oil down, add the beans and fresh thyme. Stir well and allow the beans to heat through.
Divide the oil down between 4 plates and top with 2 prawn skewers per plate. Sprinkle with chopped coriander.