Brown the meat on the stove top. Add a bit of salt, pepper and about 1/2 teaspoon of minced garlic for flavor.
Scoop out the seeds of the spaghetti squash and pressure cook it on high for about 15 minutes. You will need to add about 1 cup of water to the pressure cooker and seal the pressure top lid first. Once it's done, you can do a quick release of the pressure and remove the squash from the pot.
I added Kerrygold butter to the hot spaghetti squash and then used a fork to shred it.
I added about 1/4 cup of spaghetti squash to 2 oz of hamburger for each half spaghetti squash.
Finally, I topped mozzarella cheese on the top and let it sit for about 5 minutes. The squash was hot enough to melt the cheese after that time. You could also add the squash to the oven for about 5 minutes on 350 to melt the cheese too if needed.