Cook the onion in two tablespoons of the oil over medium heat until golden brown. Reserve and keep warm.
Combine the remaining six tablespoons of olive oil, olives, mint, parsley, tomatoes and lemon juice in a bowl with a little sea salt and plenty of black pepper.
Char grill the bread slices and rub with cut clove of garlic.
Fry the haloumi on both sides on a very clean flat plate over high heat until it browns.
Place the grilled bread on four small plates. Top with the raddiccio then the cheese, then scatter the onions over the cheese. Spoon the dressing over the top and serve immediately.