Preheat the oven to 400ºF and line a baking sheet with parchment paper to prevent sticking and promote even roasting.
Trim off both ends of the delicata squash, then carefully slice it in half lengthwise. Using a sturdy spoon, scoop out the seeds and any fibrous strands from the center, ensuring a smooth, clean interior. Next, cut the squash into uniform ½-inch thick slices, creating crescent-shaped pieces that will roast evenly.
Arrange the squash slices on the prepared baking sheet. Drizzle with olive oil, ensuring each piece is lightly coated, then sprinkle with salt, garlic powder, and black pepper. Use your hands or a spatula to toss everything together, making sure the seasoning is evenly distributed. Spread the slices out in a single layer to allow for proper caramelization.
Place the baking sheet in the preheated oven and roast for 20 minutes. Once the squash has developed a golden hue on one side, flip each piece over using tongs or a spatula. Continue roasting for another 10–15 minutes, or until the edges are deeply browned and the squash is tender.
Before serving, taste and adjust the seasoning if needed. Serve warm and enjoy the naturally sweet, nutty flavor of this perfectly roasted delicata squash.