Pre-heat the oven to 400°F.
Halve the squash lengthwise and place cut-side down on baking sheets. Roast for about 1 hour, or until tender; turn cut-side up and shred the squash into spaghetti-like strands with the tines of a fork; season with salt and pepper.
Add all the ingredients except the salt to a food processor and puree. Season with salt, to taste.
Pour the sauce over spaghetti squash or cooked gnocchi and toss to combine.