Preparation

• Position a rack in the center of the oven and heat the oven to 375°F.
• Slice 1/4 cup of the spinach into thin ribbons and set aside.
• Bring a large pot of well-salted water to a boil, and cook the lasagne according to package directions until al dente. Drain well and pat dry with paper towels.
• Meanwhile, in a 12-inch nonstick skillet, heat 1 Tbs. of the oil over medium-high heat. Add the prosciutto and cook, stirring occasionally, until crisp and browned in spots, 2 to 3 minutes. Transfer to a paper-towel-lined plate and crumble when cooled.
• Add the remaining 1 Tbs. olive oil to the skillet, then add the mushrooms, onion, 3/4 tsp. salt, and 1/4 tsp. pepper; cook, stirring occasionally, until browned, 4 to 5 minutes. Add the garlic and cook until fragrant, about 30 seconds. Add the spinach by the handful and cook, stirring often, until wilted. Set aside until cool enough to handle. Season to taste with salt and pepper.
• Lightly oil an 8×8-inch square or 8-inch round baking dish. In a medium bowl, combine the Scamorza, Grana Padano, and rosemary. Set aside 1/2 cup.
• Spread one of the noodles with about cup of the spinach mixture and 1/4 cup of the remaining cheese mixture. Roll up the noodle from the short end and transfer to the prepared dish, positioning it upright with its seam against the side of the dish. Repeat with the remaining noodles, filling, and cheese, arranging the rolls around the outside of the dish first before filling in the center. Sprinkle with the reserved cheese mixture. Bake until the cheese is golden brown, 25 to 35 minutes.
• Remove the rolls from the dish, cut each in half crosswise, and arrange on plates. Crumble the prosciutto over the rolls, and top with the spinach ribbons and a drizzle of the vinegar before serving.