For the chicken, remove the needles from the rosemary and chop finely. Take the bare woody rosemary stem and sharpen the thickest point to create a skewer.
Flatten the chicken halves slightly with a meat mallet or rolling pin, then season with salt and freshly ground black pepper and sprinkle with the chopped rosemary needles.
Place one slice of fontina on top of each chicken piece, followed by the prosciutto.
Secure the stack with the rosemary branch as you would with a skewer or wooden toothpick.
For the courgettes drizzle one tablespoon of the olive oil into a small ovenproof dish.
Arrange alternate slices of tomato and courgette overlapping each other in the dish and season with salt and freshly ground black pepper.
Drizzle with another one tablespoon olive oil, sprinkle with the marjoram leaves and top with parmesan.
Place into the oven to bake for 4-5 minutes, until the cheese begins to melt and turn golden.
Meanwhile, dredge the bare side of the chicken with plain flour and shake off any excess.
Heat the butter and olive oil in a frying pan over a medium heat. When the butter is foaming add the chicken, flesh-side down first and cook on a medium heat for about two minutes, or until golden-brown, then turn the breast over and cook for one minute on the prosciutto side, until golden.
Turn the chicken breast over again and add the wine to the pan. Heat to boil and reduce the liquid until almost entirely evaporated. Check the chicken breast is completely cooked through, then remove the chicken and place on a plate to rest.
Add a small knob of butter to the pan and melt to thicken the sauce.
Remove the courgettes and tomatoes from the oven and drizzle with the remaining tablespoon of the olive oil before serving.
Pour the sauce over the rested chicken and serve immediately with baked courgette and tomato.