Tear the bread into rough lumps and place in a large bowl with the onion, cucumber and tomato. Add a splash of olive oil and vinegar and season with salt and pepper. Mix and sprinkle the basil over the top.
Heat a little olive oil in a frying pan and then add the cheese. Turn when it forms a crust and cook the other side.
Serve the salad on plates and top with the haloumi and a drizzle more olive oil.