Cut the squash in half lengthwise. To help with this, use a knife to puncture the skin of the squash a number of times all over. Microwave on high for 3-4 minutes to soften the squash. Use a chef's knife to carefully cut the squash in half. (Make sure your cutting surface is secure).
Scoop the seeds out and brush the flesh with oil and season with salt, onion powder and pepper.
Place the squash halves cut side up in the air fryer basket.
Air fry at 350F for 20-25 minutes, or until the squash is fork tender.
Use a fork to pull apart the cooked squash flesh so it resembles strands of spaghetti.
Serve the noodles warm on their own or with your favorite toppings.
Notes
If you soften the squash in the microwave, make sure you poke holes in the squash so steam can escape. If you don't, the squash may explode in the microwave.
Roast the squash cut side up so the oil and seasonings don't drip out of the basket.
Make sure your spaghetti squash will fit in your air fryer. I recommend using small ones that are 2 1/2 pounds or less.
Air frying time will vary depending on how large your squash is and the size, brand and model of your air fryer.
I used a Cosori 5.8 quart air fryer and two squash halves fit nicely in the basket. If you have a smaller air fryer, you will need to buy a smaller squash or air fry the halves separately.