Prepare the marinade by putting Aceto Balsamico di Modena (Balsamic Vinegar of Modena), bay leaf,  sage, chopped celery, juniper berries crushed in a mortar, half a lemon zest and peeled and chopped shallots in a bowl. Put the beef slices in to marinate and let stand for 2 hours. Prepare the filling. Put the ricotta in a bowl, and add the beans. Season with salt and pepper and mix the ingredients. Remove the beef from the marinade. Spread out the slices and distribute the filling.
Put a knob of butter on each roll and roll up the meat. Fold the ends of the rolls and wrap the rolls tightly in oven paper. Tie each roll, put in the oven at 160 ° C and cook for 10-12 minutes.
Remove them from the oven and let cool. Put the vinegar- Aceto Balsamico di Modena IGP- marinade into a saucepan and add a teaspoon of sugar and reduce to half. Serve the rolls scallopped on a bed of lettuce. Season with a few drops of the balsamic vinegar reduction and extravirgin olive oil.