Mix all the marinade ingredients together.
Thread your skewers: first monkfish, then one piece each of onion, pepper, tuna, courgette and finally prawn. Make up all the skewers, then place them in a long, deep dish and cover with the marinade. Leave for a couple of hours, twisting the skewers round occasionally so that everything gets covered.
Heat your barbecue or grill, or put a pan on to heat, and cook the skewers with a little olive oil, turning them to colour all sides.
Whisk together the olive oil, vinegar and salt to make a dressing, and dress the rocket or watercress with it.
Serve the skewers on top of a piece of toast to soak up all the juices, with the chilli scattered over and the salad on the side. The way to eat this is to take one bite from the skewer, then one bite of bread.