Soak the dried mushrooms in 1l water for half an hour. If they haven't soften by then, leave for longer.
Use a blotted spoon to take the mushrooms out. Wash them thoroughly and drain the soaking water through a fine mesh to get rid of sand. Keep both.
Remove the seeds from the squash and stuff in the garlic cloves.
Brush the squash (open side) with 1 tbsp olive oil mixed with 1 tsp dried thyme and 1/2 tsp salt.
Roast in the oven for about 30 minutes until soft.
Remove, scoop out the flesh and squeeze out the garlic.
Blend together with 100ml stock and 100ml cream, if using. Add more stock to adjust consistency. Taste and adjust for salt.
Heat 50g butter in a pan, add 3 garlic cloves, fresh thyme and mushrooms and sauté for a few minutes.
Add 1/2 cups of mushroom water and salt and simmer for 30-35 minutes. Add more soaking water if needed.
Discard the aromatics, add the blended squash to the pan and stir to combine.
Squeeze over the lemon juice from one wedge. Taste and adjust to perfection.
To make crispy sage leaves, heat a little olive oil to medium and fry the leaves for just about 20 seconds on each side.
Boil pasta according to the instructions. Transfer to the pan with the sauce and toss to coat.
Serve immediately with grated parmesan, freshly ground black pepper and garnished with fried sage leaves.