In a medium bowl, combine the garlic, scallions, parsley, salami, Fontina, Parmigiano, and bread crumbs and mix well. Add ¼ cup of the olive oil and mix well with your hands or a spoon. Set aside.

Cut six 15-inch-long pieces of kitchen twine. Open out the beef, season on both sides with salt and pepper, and place it on a work surface so a long side is toward you. Spread the bread crumb mixture evenly over the beef, leaving a ½-inch border along the side farthest from you; press and gently pack the stuffing mixture onto the beef to keep it in place (you may have a little stuffing left over–it makes a great panini filling). Starting from the side nearest you, roll up the meat like a jelly roll, pressing any stuffing that falls out of the ends back into the roll, and tie tightly with the twine, spacing the ties evenly (it’s easier if you have a friend to tie the beef while you hold the roll together). Wrap tightly in plastic wrap to make a compact roll, and place in the refrigerator for at least 2 hours, or as long as overnight.

Preheat a gas grill or prepare a fire in a charcoal grill.

Carefully unwrap the beef roll and, using a very sharp knife, cut it between the ties into six thick pinwheels. Brush gently on both sides with the remaining 3 tablespoons olive oil and season with salt and pepper.

Gently lay the pinwheels on the hottest part of the grill and cook, unmoved, for 5 to 7 minutes. Using a spatula, carefully turn each pinwheel over and cook for about 4 minutes longer for medium-rare. (Don’t be alarmed if some of the cheese in the stuffing starts to melt and char on the grill, making kind of a savory Florentine-cookie-like thing; but if you find it charring too much, move the pinwheels to a slightly cooler part of the grill.) Transfer to a platter and serve.