Preheat oven to 425 degrees. Line a rimmed baking sheet with parchment paper or aluminum foil for easy cleanup.
Peel butternut squash and cut in half lengthwise. Scoop out the seeds and discard. Cut into 1 1/2-inch cubes. You will have about 7 cups of butternut squash cubes, more or less depending on your exact squash size.
In a large bowl, add butternut squash. Drizzle with olive oil and sprinkle with thyme, salt, and pepper (I like 1/2 teaspoon salt and 1/4 teaspoon pepper). Toss until evenly coated. Spread in an even layer on prepared baking sheet.
Roast until the squash is tender and starting to caramelize, about 20 to 25 minutes, stirring after 15 minutes.
Squash: Choose a butternut squash that is firm to the touch and doesn't have any soft spots. For more information on prep, see my full tutorial on how to cut butternut squash.
Thyme: Fresh rosemary and sage are also delicious on squash.
Yield: 2 pounds butternut squash yields about 4 cups, peeled and cubed, enough for four 1-cup servings.
Storage: Store leftovers covered in the refrigerator for up to 4 days. Leftover roasted butternut squash is great tossed into salads, meal prep containers, or reheated as a side dish the next day.