Bring a large pot of water to a boil and line a sheet pan with parchment paper. Add 2 teaspoons of salt, then add lasagna sheets and cook until al dente. Drain lasagna sheets, then set overlapping on the prepared sheet pan so they don’t stick together.,

Preheat the oven to 375°F. Line a large baking sheet with parchment paper.,

Toss the butternut squash cubes with olive oil, sage, thyme, salt, and pepper on the prepared baking sheet. Spread them out and roast for 30-35 minutes, or until tender and slightly caramelized.,

When the butternut squash is done cooking, transfer them to a high-speed blender along with the milk and blend until smooth and creamy. It will make 4-5 cups of sauce.,

In a bowl, combine ricotta cheese, Mozzarella or Parmesan cheese, egg, garlic, basil, salt, and pepper. Mix well and set aside.,

Add 1 cup of the butternut squash sauce on the bottom of a 9×13-inch baking dish and spread into an even layer. Add a layer of lasagna sheets, followed by about ¾ cup of the ricotta cheese mixture, smoothing it into a somewhat even layer. Add 1 cup of the squash sauce on top of the ricotta cheese mixture, then top with about ½ cup of mozzarella, and finally another layer of lasagna sheets.,

Repeat this process two more times so you have a total of three layers. Add remaining squash sauce on top of the final layer of lasagna sheets, followed by remaining mozzarella.,

Cover with foil and bake in the preheated oven for 30 minutes. Remove the foil, and bake for an additional 20 minutes or until the cheese is golden and bubbly. Let rest for 15 minutes before slicing and serving.