Bring a large pot of salted water to a boil. Add the lasagna noodles and cook according to package instructions until al dente. Drain and rinse with cold water to stop the cooking process. Lay the noodles flat on a clean kitchen towel or parchment paper to prevent sticking.
Heat olive oil in a large skillet over medium heat. Add the minced garlic and sauté for about 30 seconds, until fragrant. Toss in the chopped spinach and cook until wilted, about 2-3 minutes. Remove from heat and allow to cool slightly.
In a mixing bowl, combine the ricotta cheese, half of the shredded mozzarella, grated Parmesan, sautéed spinach and garlic, dried oregano, salt, and pepper. Mix well until all ingredients are evenly distributed.
Preheat your oven to 375°F (190°C). Spread about 1/4 cup of marinara sauce evenly on the bottom of your baking dish. Carefully spread roughly 2-3 tablespoons of the spinach and ricotta filling onto each lasagna noodle, then roll each noodle up tightly. Place the roll-ups seam side down in the baking dish.
Pour the remaining marinara sauce over the roll-ups, then sprinkle the remaining mozzarella cheese on top. Cover the baking dish with foil and bake for 25 minutes. Remove the foil and bake for an additional 10 minutes until the cheese is bubbly and golden brown.
Let the roll-ups rest for 5 minutes before serving. This allows the cheese to set slightly, making them easier to serve. Pair with a fresh green salad or some crusty bread for a complete meal.
