Preheat oven to 400°F. Grease a baking dish with nonstick cooking spray and set aside.
Cut the butternut squash carefully in half lengthwise using your sharpest knife. If the squash feels too firm to cut safely, microwave it whole for 2 minutes first to soften the skin slightly. Use a metal spoon to scrape the seeds and stringy bits from the cavity and discard.
Drizzle the cut flesh side with olive oil and use a pastry brush to spread it evenly to the edges. Season with salt and black pepper. Place both squash halves face down in the baking dish.
Pour about 2 cups of water into the dish so it sits at least 1 inch deep around the squash. This steam is what keeps the flesh soft and scoopable — do not skip it.
Bake for 35 to 40 minutes or until a fork pressed through the skin side slides in with no resistance. Larger squash may need up to 50 minutes — go by feel, not the clock. Remove from oven and let sit for 5 minutes before scooping. The rest makes the flesh easier to scoop cleanly.
Use a large spoon to scoop the flesh away from the shell in long strokes. Discard the shell.
Serve with butter and a pinch of salt, or see the seasonings section for more options.
Notes
Sweet Flavors - Cinnamon and nutmeg
Savory Flavors - Sea salt and garlic, balsamic, kosher salt, Italian seasoning or lemon, and extra virgin olive oil.