Butter bread and arrange cheese over half of the slices, buttered side down. Sprinkle with chives and cover with remaining slices, buttered side up. Preheat a griddle or large non-stick frying pan and cook sandwiches two at a time 2 minutes each side until golden brown and cheese has melted. Keep hot. To serve, cut the cheese toasts into fingers. Serves 4 to 6.