Preheat the oven to 400°F
Wash and dry the butternut squash
Cut off both ends
Peel the skin with a vegetable peeler
Slice the squash in half lengthwise
Scoop out the seeds
Cut the squash into cubes or leave it in halves
Toss with oil and salt if desired
Spread on a baking sheet in a single layer
Roast for 25 to 45 minutes, depending on size
Flip halfway through for even browning
Roast until fork-tender and lightly browned
Remove from the oven and serve