Each component of this satisfying vegetarian main dish can be made in advance: the roasted squash, the sweet-and-savory Middle Eastern-style stuffing, and the snappy pomegranate relish.
Preheat oven to 425 degrees. Brush a baking sheet with oil. Mix together 1 1/2 teaspoons salt, 1/2 teaspoon pepper, cumin, and coriander; sprinkle inside of squashes with spice mixture. Place squashes on sheet, cut-sides down, and roast until just tender, about 20 minutes. Turn cut-sides up and fill with stuffing, mounding slightly (you should use about 3/4 cup in each squash half). These can be made ahead and refrigerated, covered, up to 1 day; bring to room temperature before baking. Bake, covered with parchment-lined foil, until heated through, about 15 minutes. Serve, with relish and sprinkled with toasted almonds and parsley.