How to Make It
Preheat the oven to 425°. Place the walnuts on a baking sheet and toast in the oven for 10 minutes, or until they are light brown and fragrant.
In a medium bowl, whisk together the pumpkin, sage leaves, sea salt, chile flakes, 1/2 teaspoon of freshly ground pepper, white balsamic vinegar, garlic and 1 cup of water.
In another medium bowl, whisk together 1 cup of the ricotta, the eggs, 1/2 teaspoon of freshly ground pepper and 1/4 cup water.
In a 9-by-11-inch ovenproof baking dish, spread 1/3 cup of the pumpkin and cover with 4 lasagna noodles, 1/3 of the pumpkin and 1/3 of the ricotta. Continue to layer the lasagna, sprinkling all of the walnuts in the middle layer. Dot the top of the lasagna with the remaining 1/2 cup of ricotta cheese.
Cover the baking dish with aluminum foil and bake in the preheated oven for 35 minutes. Uncover the baking dish and spoon the pan juices over any noodles that are not in the liquid. Bake for 10 minutes, until the noodles are soft.
Remove the lasagna from the oven and set it aside to rest for 10 minutes before serving.