Halve 1 large unpeeled butternut squash (about 3 pounds) and cut into thick wedges, discarding the seeds. Toss with olive oil and roast at 400 degrees F until soft, 35 to 45 minutes. Remove the skin. Puree the squash with 3 tablespoons butter; season with salt. Warm a few tablespoons of maple syrup with a pinch of cayenne pepper; drizzle over the mash.
Use a food processor or immersion blender to puree these veggies-they're too fibrous for a potato masher.