Lay meat out on a surface, season with pepper and top each with a slice of cheese, prosciutto and a sage leaf.
Roll up and pin with a small wooden skewer.
Melt the butter and cook the onion in it until it becomes transparent. Add the meat rolls and fry on all sides. Mix the spinach with the whipped cream and the Parmesan cheese, place the meat on top and roast in the oven heated to 160 °C for 15 minutes.
Tip: Did you know that one bowl of spinach already covers the entire daily requirement of vitamin K and beta-carotene?