Roast the Sweet Potatoes: Preheat your oven to 400°F (200°C). In a medium bowl, toss the cubed sweet potatoes with extra virgin olive oil, cinnamon, maple syrup, sea salt, and black pepper. Spread across a lined baking sheet in a single layer and roast for 20–25 minutes until the edges are beautifully caramelized and the centers are soft. Remove and allow to cool slightly.
Boil the Pasta: Bring a large pot of salted water to a rolling boil. Cook the lasagna sheets according to package instructions, pulling them out 1-2 minutes early so they stay firmly al dente. Drain carefully and lay each sheet out flat on parchment paper or clean, damp towels to prevent sticking.
Mix the Cheese Filling: Heat a tiny touch of olive oil in a skillet over medium heat and sauté the chopped baby spinach for 1-2 minutes until just wilted. Remove from heat, let cool, and squeeze out all excess water using a paper towel. In a medium bowl, mix together the ricotta, mozzarella, finely chopped dried cranberries, the thoroughly drained spinach, chopped fresh rosemary, lemon zest, and a light pinch of salt and pepper.
Assemble and Roll: Place a single lasagna noodle completely flat on your work surface. Spread a generous, even layer of the creamy ricotta mixture down the full length of the noodle, leaving a small border at the far end. Scatter a line of the roasted sweet potato cubes and a few whole cranberries over the top. Roll the lasagna sheet up firmly from one end to the other into a tight cylinder. Repeat for all remaining noodles.
Bake to Perfection: Arrange the rolls neatly seam-side down in a baking dish lightly greased with olive oil. Sprinkle a light touch of extra mozzarella or Parmesan over the tops. Bake at 375°F (190°C) for 15–20 minutes until the edges turn a crisp golden brown and the cheese is bubbling.
Garnish and Serve: Transfer the hot rolls carefully to a serving plate. Crown each individual roll with a fresh sprig of rosemary and a vibrant whole cranberry, then give the entire platter a snow-like dusting of finely grated Parmesan cheese before serving hot.