Put the pumpkin pieces on a baking sheet and toss with oil, garlic,onion, half the sage and thyme, and the nutmeg. Season with salt and pepper, then roast in the oven until tender and golden.
Remove from the oven and allow to cool a little (but keep the oven on). Discard the garlic and put the mixture in a bowl.
Add the chives and ricotta and mash everything together.Meanwhile, cook the lasagna sheets in a large pot of salted boiling water until just al dente.
Drain and cook under running water. Lightly brush the sheets with oil on both sides so they don’t stick together and lay them on a plate.Oil or butter a baking dish and pour a little of the cream into the base.
Place 2 lasagna sheets over the cream.
Spread some of the pumpkin mixture over the top and scatter with some asparagus, then with some of the remaining sage and thym, then the grana padano.
Add more cream and lasagne sheets and continue layering. Top with the final pieces of lasagne, the remaining pumpkin, asapargus, cream and grana padano. Scatter with the remaining thyme and press the last sage leaves over the surface.
Bake for 30 to 40 minutes, or until golden. Rest for 15 minutes before serving.
