Preheat your oven to 400℉ and line a large baking sheet with parchment paper or a silicone baking mat.
Wash and dry your squash to be sure it is free of all dirt. Place the squash on a stable cutting surface.
Hold one end of the squash firmly down on the cutting surface, being sure your hand is not close to the middle of the squash (where you intend to cut). Insert the tip of your sharp paring knife into the middle of the squash. Gently push the knife down towards the cutting surface. Rotate the squash around a bit and again pull the knife down (carefully) towards the cutting surface. At this point, the squash should easily crack apart, exposing the inedible seeds inside.
Scoop out and discard seeds.
Brush the inside flesh of the squash with the oil and season with salt.
Place the two halves of spaghetti squash cut side down on your prepared baking sheet.
Cook for 35-40 minutes. Your squash is done when the outside is starting to turn golden brown and the strands inside easily pull away with a fork.
Allow squash to cool a bit until it is safe to handle. Once you can, flip your cooked squash over.
Use a fork to rake the strands apart and scoop them out of the squash's shell.
Enjoy the squash strands warm with butter, a little extra oil, pasta sauce, or in your favorite spaghetti squash recipes (see blog post for ideas).
Allow leftovers to cool and store in fridge for up to 5 days. Freezing is not recommended.