Prep the vegetables and make the filling: Place oven rack in center position. Heat oven to 375 degrees F.
Trim the tough ends off asparagus and discard. Slice the tips off and set them aside. Slice the remaining asparagus stalks crosswise into ¼‑inch rounds.
In a large bowl toss squash, onion, garlic, half the sage, half the thyme and a pinch of nutmeg with olive oil. Pour the mixture onto a rimmed parchment-lined baking sheet. Season with salt & pepper, then roast in the oven until very soft and lightly caramelized, about 45 minutes. You may need to stir the vegetables and rotate the baking sheet halfway through to assure even roasting.
Remove squash mixture from oven. Turn off oven. Discard garlic pieces and put the mixture into a large bowl. Add asparagus rounds (but not the tips) to bowl, followed by chives and ricotta. Use a fork or potato masher to mix everything together into a rough mash.
Make the besciamella: Heat 4 tablespoons melted butter in a medium heavy-bottomed saucepan set over medium heat. Once it becomes frothy whisk in ⅓ cup flour until a thick paste forms, about 1 minute. Slowly add 2 ⅓ cups milk whisking almost constantly until it begins to thicken and bubble, about 2 minutes. Reduce heat and simmer whisking often, 2 more minutes. Remove from heat and season with salt & pepper. Cover and set the besciamella sauce aside, kept warm. May also be made up to 2 days ahead to this point, brought to room temperature then kept covered and refrigerated. In which case, return the sauce to a spreadable consistency by gently reheating it with about 1 tablespoon milk before using.
Make the crespelle batter: Mix 3 tablespoons melted clarified butter, eggs, remaining 1 cup flour, remaining 2/3 cup milk and ¼ teaspoon salt together in a blender until lightly frothy, about 20 seconds. Pour the batter into a bowl. Adjust consistency by adding up to 2 tablespoons sparkling water, stirring to incorporate. You want a velvety texture that is just thick enough to coat the spoon. Refrigerate batter at least 30 minutes and up to 1 day before proceeding.
Make the crespelles: Lightly brush a 8 or 9‑inch nonstick skillet or crepe pan with some of the remaining 2 tablespoons melted butter. Place pan over medium heat. Allow the pan to get hot but not smoking. Ladle ¼ cup batter into the center of the pan and then tilt the pan in all directions to cover the bottom evenly. Cook about 1 minute, or until browned on the bottom. Turn and cook briefly on the other side. Slide the crespelle onto a paper towel lined plate to cool. Use the rest of the batter to make more crespelles in the same manner, brushing skillet with melted butter as needed. You will only need 4 crespelles for this torta. Choose the 4 best and set them aside. Enjoy the others with some sugar, butter and a spritz of lemon. The crepes may be made up to 2 days ahead kept with sheets of parchment or wax paper between them; covered and refrigerated. Bring to room temperature before continuing.
Make the torta: Place oven rack in center position. Heat oven to 400 degrees F.
In a medium bowl mix together the grated Fontina, grated Parmesan, remaining sage and thyme. Set aside.
Brush the inside of an 8 or 9‑inch springform pan with some of the remaining melted clarified butter. Place 1 crespelle on the bottom of the pan. Trim it if necessary so it lays flat. Spoon in about ¼ of the warm besciamella sauce, spreading it evenly with the back of the spoon, then dollop about ¼ of squash filling covering the pan evenly. Make 3 more layers in the same manner. Sprinkle cheese mixture evenly over the top, followed by reserved asparagus tips.
Bake uncovered, until top is bubbling and golden, about 30 minutes. Let the torta rest on a wire rack about 15 minutes. Remove the sides of the springform pan. Cut into wedges. Serve warm.
I just answered my own question by Googling crespelle; it’s an Italian crepe. Looking forward to trying this recipe.