Slice prosciutto, tomatoes and 4 tablespoons of olives, pluck the rosemary and finely chop.
Mix all together. Place roulades on your work surface and season with salt and pepper. Spread with filling, roll and fix on wooden skewer. Peel onion and garlic and chop finely. Cut remaining olives roughly.
Heat olive oil in a big pan and brown the roulades. Then remove from the pan.
Place the onion and garlic in the pan. Add Marsala, then tomatoes and the remaining olives.
Finally add the roulades and cook for about 40 minutes until tender.