Kabocha Squash Sauce:

• 2 tablespoons olive oil
• 1 2-lb. kabocha or butternut squash, peeled, seeded, cut into ½” pieces (about 3 cups)
• 1 small onion, chopped
• 2 cloves garlic, chopped
• 1 tablespoon finely chopped fresh sage
• Salt and freshly ground black pepper
• 2 cups low-sodium chicken or vegetable stock

Ricotta Filling:

• 1 pound fresh ricotta, drained
• Pinch of freshly grated nutmeg
• 1 teaspoon freshly grated lemon zest (from about 1/2 a lemon)
• 1 cup freshly grated Parmigiano-Reggiano
• 1 large egg
• Salt and freshly ground black pepper

Additional Ingredients:

• 1 package lasagna noodles
• 1–2 cups fresh mozzarella, shredded or sliced
• Crispy sage leaves to finish, if desired