Transfer the cubed sweet potatoes to the prepared baking sheet and drizzle them with olive oil. Sprinkle with cinnamon, sea salt, black pepper, and half of the minced garlic. Toss everything together thoroughly until every piece is evenly coated with seasoning and oil. Spread the sweet potatoes out into a single layer with a little space between the cubes to encourage golden roasted edges and prevent sogginess.

Roast the sweet potatoes for 28–35 minutes, flipping them halfway through cooking for even browning. They should become fork-tender with lightly caramelized edges and a rich roasted aroma. Avoid overcooking them into a mushy texture because you still want some structure inside the lasagna rolls.

While the sweet potatoes roast, bring a large pot of generously salted water to a rolling boil. Add the lasagna noodles carefully and cook until just al dente according to package instructions. Stir occasionally during cooking so the noodles do not stick together. Once cooked, drain them gently and lay them flat on parchment paper or a lightly oiled surface to prevent tearing and sticking.

In a large mixing bowl, combine the ricotta cheese, chopped spinach, parmesan cheese, fresh thyme, and the remaining minced garlic. Stir everything together until creamy and evenly mixed. If the ricotta seems watery, let it drain for a few minutes beforehand so the filling stays rich and thick rather than runny.

Remove the roasted sweet potatoes from the oven and allow them to cool slightly so they are easier to handle. Lightly mash them with a fork or potato masher, leaving a little texture instead of making them completely smooth. Stir in the dried cranberries so their tart sweetness gets evenly distributed throughout the filling mixture.

Place one cooked lasagna noodle flat on a clean surface and spread a layer of the ricotta mixture evenly across the noodle from end to end. Add a spoonful of the sweet potato and cranberry mixture over the ricotta layer, spreading it gently without overfilling. Keeping the filling balanced helps the rolls stay intact while baking.

Starting from one end, carefully roll each noodle into a tight spiral without squeezing out the filling. Place each roll seam-side down into a lightly greased baking dish so they stay secure during baking. Continue until all the rolls are assembled and neatly arranged in the dish.

Drizzle the tops lightly with olive oil to help them stay moist while baking. Sprinkle extra parmesan cheese over the rolls for a golden, savory finish. You can also add a pinch of black pepper, fresh thyme, or red pepper flakes for extra flavor and color.

Cover the baking dish loosely with foil and place it into a preheated 375°F oven. Bake for 20 minutes so the filling heats through evenly and the flavors blend together beautifully without drying out.

Carefully remove the foil and continue baking for another 10 minutes until the tops become lightly golden and slightly bubbly around the edges. Watch closely during the final minutes to avoid overbrowning the cheese.

Remove the baking dish from the oven and let the lasagna rolls rest for 5–10 minutes before serving. This resting time helps the filling set properly, making the rolls easier to plate while allowing the flavors to settle and deepen.