Preheat oven to 375 degrees. Lightly grease a 9 x 13 inch baking dish.
Melt the butter in a small saucepan over medium heat. Add the sage leaves and rosemary sprigs and cook until slightly crisp, about 2 minutes. Remove. Stir in the garlic and chopped oregano. Whisk in the flour until no large clumps remain.
Slowly stream in the whole milk and cider, whisking constantly, until fully used. Crank up the heat and bring to a boil for 4-5 minutes until the sauce thickens. Stir in the kale until wilted, about 1-2 minutes more. Remove from the heat. This is your bechamel sauce.
Place the pumpkin puree in a bowl and blot well with paper towels to remove excess moisture. Stir in the ricotta, egg, cinnamon, nutmeg, and parmesan cheese. Season with salt and pepper.
Pour 1/4 of the bechamel sauce into the bottom of the casserole dish. Layer 3-4 lasagna noodles overtop. Spread 1/3 of the ricotta over the noodles - don't worry about being too precise! Sprinkle with a handful of the shredded Gouda. Pour over another 1/4 of the sauce, then layer noodles, ricotta, and Gouda. Repeat until all of the filling and sauce is used up. Spread the rest of the Gouda overtop.
Cover the dish with foil, set the dish on a baking sheet to catch any spills, and bake for 30 minutes, then remove the foil and bake an additional 15-20 minutes until the cheese is bubbly and golden in spots. Let the lasagna rest for 10 minutes, then slice and serve warm!