Step 1
Preheat the oven to 400 degrees. Place the squash on a sturdy cutting board. Cut off the stem and bottom end of the squash. Then carefully cut the squash in half lengthwise. Use a spoon to scrape out all of the seeds and stringy bits.
Step 2
Cover a baking sheet with parchment paper. Brush the squash with olive oil on the cut side. Sprinkle lightly with salt and pepper, not using too much salt since it can prevent it from caramelizing.
Step 3
Place the squash cut side down on the baking sheet and roast for 40-45 minutes until it is fork tender. For less browning, roast the squash cut-side up. Don't worry about the darkened edges on the skin, that's where all the deep flavor develops. It isn't burnt.
Step 5
Optional: During the last 10 minutes of roasting, flip the squash so the flesh side is up. Brush with melted butter and sprinkle with 1 tablespoon of brown sugar (or honey or maple syrup) and 1/2 teaspoon of cinnamon.