Preheat the oven to 375 degrees Fahrenheit. Line a roasting pan or rectangular baking dish with foil or parchment paper. Pierce the uncooked squash all over with a sharp knife.
Place whole squash in the prepared roasting pan or baking dish and bake for 45-60 min. Carefully flip halfway through baking.
Allow it to rest for 10 minutes. Then transfer to a cutting board and slice in half lengthwise (wearing pot holders if needed).
Scoop out the seeds from each half and then use the tines of a fork to pull strands of the flesh apart.Store in an airtight container in the refrigerator for 3-4 days.
Notes
Use a roasting pan or baking dish that has higher sides than a rimmed baking sheet.
Be careful when flipping midway through cooking. Using oven mitts is highly recommended! The outer shell will begin to soften as it cooks.
Cooking time will vary based on the size of your squash. Large ones yield about 7-8 cups of tendrils/noodles while medium ones can yield about 4-6 cups.