Select the sauté option on the instant pot. Add in olive oil. Once you start to hear it sizzle add in onion and cook until golden brown 3-4 minutes.

Add in ground beef and cook until browned, 2-3 minutes (doesn't have to be fully cooked through, we just want to get some color on the beef)

Add in garlic and cook for an additional minute.

Add in the spaghetti sauce, fire roasted tomatoes and water.

Layer in the halved spaghetti noodles, rotating which direction they are in (this helps to keep the noodles from clumping up when cooking)

Place the lid back on and press manual mode or high pressure. Set to 6 minutes.

Once done release the valve and wait for all of the steam to stop.

Remove lid and stir the spaghetti.

Season with salt and pepper to taste.

Serve with basil and parmesan cheese, if desired.