Preheat the oven to 400°F.

Cut the squash in half lengthwise and scoop out the seeds with a spoon. Place the halves cut side up in a baking dish with ½ inch of water. Cover tightly with foil and bake until the flesh is easily pierced with a fork, 40 to 45 minutes. (If your knife isn't up to cutting the raw squash, wrap the whole squash in foil and bake it until tender, 45 to 60 minutes depending on size, then halve it and scoop out the seeds.)

While the squash bakes, toast the almonds or walnuts in a dry skillet over medium-low heat, stirring often, until golden and fragrant, 3 to 5 minutes. Transfer to a plate so they don't keep browning.

When the squash is just cool enough to handle, scrape the flesh lengthwise with a fork to pull it into spaghetti-like strands, and transfer them to a mixing bowl. Leave a thin layer of flesh in each shell so the shells keep their shape.

Melt the vegan buttery spread (in the microwave or in the same small skillet over low heat) and stir in the curry powder. Pour it over the squash strands, add the scallions, parsley and dried cranberries, and toss well. Season to taste with salt and pepper.

Pour any water out of the baking dish. Pile the squash mixture back into the shells, return them to the dish, and bake uncovered until heated through, 8 to 10 minutes.

Scatter the toasted nuts over the top, cut each squash half crosswise into 2 portions, and serve.