Preheat your oven to 400°F (200°C).
Prepare the squash: Wash the Butterkin squash thoroughly. Using a sharp knife, cut off both ends of the squash. Peel the squash using a vegetable peeler. Slice it in half lengthwise, then scoop out the seeds using a spoon. You can save the seeds for roasting separately if desired.
Cut the squash: Cut the squash into even cubes or wedges, depending on your preference. Uniform pieces ensure even cooking.
Season the squash: In a mixing bowl, toss the squash pieces with olive oil, salt, black pepper, cinnamon, and paprika. Ensure all pieces are well-coated with the seasoning.
Roast the squash: Spread the seasoned squash pieces in a single layer on a baking sheet. You can line the baking sheet with parchment paper or aluminum foil for easy cleanup. Roast in the preheated oven for 25-30 minutes, or until the squash is golden brown and tender, flipping halfway through for even roasting.
Serve: Remove the squash from the oven and let it cool slightly. Garnish with fresh rosemary or thyme if desired, and serve immediately as a side dish.