Split squash in half.
Remove all seeds.
Place one cup of water in the instant pot.
Place squash on top of each other open side up on a trivet.
Use the manual setting high pressure for 4 minutes. Do a quick release.
Using a fork scrape all the insides of the squash into a large bowl.
In a large pan, melt butter and add saute minced garlic about 1-2 minutes.
Add in spaghetti squash, coat with melted butter.
Sprinkle with parmesan cheese and serve.