Place the blueberries, balsamic vinegar, rosemary into a small saucepan and bring to a gentle simmer. Remove from the heat and set aside.
Heat the oil in a large frying pan over a medium heat, stir in the garlic, cabbage, 1 tbsp water and salt. Fry for 3-4 minutes, turning regularly until wilted.
Take off the heat, remove the cabbage and set aside, leaving the garlic in the pan for later.
Spread one side of each slice of the Mevalia Pane Casereccio with butter, these will be the outside of the sandwich.
Spread the other side with the mustard, layer with the cabbage, cheese and blueberries, taking care to remove the rosemary. Top with the remaining slices of Mevalia Pane Casereccio ensuring that the butter side is facing outwards, press down lightly.
Return the frying pan to a medium heat; carefully transfer the sandwiches to the pan and cover with a sheet of parchment paper, top with another frying pan and weigh it down with a couple of tins out of the cupboard. Fry for 3 minutes on one side before carefully turning the sandwich to fry the other side for a further 3 minutes.
Remove from the pan, allow to rest for 1 minute, halve and serve.
Recipe tip: you can replace the Mevalia Pane Casereccio with Mevalia Mini Baguettes or Mevalia Ciabattine, they work just as well.