Preheat the oven to 220C/425F/Gas 7.
Spear the cheese with the rosemary sprig. Place on a baking sheet and place in the oven to bake for ten minutes, or until the cheese is melted and hot inside.
Meanwhile, heat a griddle pan. Add the bread and toast for 1-2 minutes on each side. Remove the toast and brush with the olive oil.
To serve, place the melted cheese in the centre of a plate, surrounded by the toast pieces.