Heat oven to 425°F. Line a baking sheet with parchment paper if you want easy clean-up.
Cut the spaghetti squash cross-wise into 2-inch rings. You can place a kitchen towel under the squash to keep it stable on the cutting board while cutting.
Scoop out seeds. Place the spaghetti squash rings on the baking sheet. Rub or spray cut surfaces of the squash with avocado oil. Sprinkle with salt.
Roast for 20-30 minutes until edges are staring to caramelize. If you want more browning, flip the squash over halfway through the cook time.
Test the squash by poking with the fork. It should give easily. If you're in doubt, err on the side of slightly undercooked, which will give a texture more like al dente pasta rather than mushy.
Remove cooked squash to plate or cutting board to cool. Using two forks, shred the spaghetti squash away from the outside skins.