Preheat oven to 375 degrees F. Remove the peel of the squash with a vegetable peeler or with a knife.
Cut the "neck", or the skinnier part of the squash into 1/2-inch rounds and dice.
Place on a greased foil-lined baking sheet in one even layer and bake for 18-22 minutes or until soft when poked a fork.
Add to a blender and puree, adding 1/4-1/2 cup water as needed to make a smooth puree.
Serve or store in an airtight container/s in the fridge for 3-5 days. Or portion into an ice cube tray and freeze, then transfer frozen cubes to a zip top storage bag and freeze for up to 3 months.
Notes
Roast the squash until soft when poked with a fork.
Add water slowly to reach the desired smooth consistency.
Stop and scrape down the sides of the blender as needed.
Stir in 1/2 teaspoon cinnamon, 1/4 teaspoon ground ginger, 1/8 teaspoon Chinese Five Spice, 1/2 teaspoon cumin, or 1/2 teaspoon Pumpkin Pie Spice if desired to add more flavor.
Stir in apple butter or applesauce to make a slightly sweeter apple-butternut squash puree. (This is a nice topping for pancakes and waffles!)