Make pockets in the bread slices with a serrated knife. Be careful not to cut right through the bread.
Fill the pockets with the cheese mix and set to one side.
Melt the butter in a small saucepan and once melted, add the crushed garlic and parsley. Stir to combine.
With a pastry brush, brush the garlic butter over both sides of the sandwiches, making sure to cover each sandwich very well.
Place a cast iron pan over a medium heat, and add a knob of butter. Once it’s melted add one of the sandwiches. Cook until golden on the underside - about 3 - 4 minutes - and then just before you flip, add a grating of parmesan to the top, uncooked side of the sandwich. Flip the sandwich over and cook on this side for a further 3 - 4 minutes, until the cheese in the middle has melted. Finally, grate some more parmesan over the top side of the sandwich and flip, cooking for only 1 minute, or until the parmesan has melted.