If your cut of lamb is too thick (I bought a butterflied leg of lamb) then using a meat tenderizer or rolling pin, hammer it out until it is thin enough to roll up. Roughly 1.5cm / 0.6 inch.
Place a layer of spinach (or any leafy greens) on top of the lamb.
Cut the halloumi into strips and place onto the spinach.
Sprinkle fresh rosemary, salt, and pepper all over.
Roll up tightly and place toothpicks along the length of the meat to stop the lamb from opening whilst cooking.
Oil a roasting dish and roll the rolled lamb noisettes in the oil. Add more salt and pepper to your taste.
Cook at 180C/350F for 30 - 40 minutes depending on the size and thickness of the lamb. I like mine slightly undercooked in the center.
Remove from the heat and cut into 5cm/2 inch noisettes.