Prepare the Squash: Preheat the oven to 400°F (200°C). Wash and dry the acorn squash thoroughly. Cut each squash in half lengthwise, then scoop out the seeds and stringy pulp with a spoon.
Slice the Squash: Place each half cut-side down on a cutting board and slice into wedges about ¾–1 inch thick. Keep the slices similar in size so they roast evenly.
Make the Honey Butter: In a small bowl, whisk together the melted butter, honey, olive oil, cinnamon, nutmeg, salt, and black pepper until well combined.
Coat the Squash: Arrange the squash wedges in a large mixing bowl or directly on the prepared baking sheet. Brush or toss them with the honey butter mixture, making sure both sides are lightly coated.
Arrange for Roasting: Line a large baking sheet with parchment paper. Spread the wedges in a single layer, leaving space between them. Position some of the cut sides against the baking sheet to encourage caramelization.
Roast Until Tender: Bake for 20 minutes, then carefully turn the wedges using tongs. Brush with any remaining honey butter mixture and return to the oven.
Finish Caramelizing: Roast for another 15–20 minutes, until the squash is fork-tender and the edges are golden and lightly caramelized. The exact time will depend on the thickness of the wedges.
Garnish and Serve: Transfer the roasted squash to a serving platter. Sprinkle with chopped fresh parsley or thyme and toasted pecans if desired. Serve warm with any glaze remaining on the baking sheet.