Set the pot to saute and then add the olive oil and butter.
Once the oil is hot, add the garlic and gently fry until it is slightly browned.
Add the red pepper flakes and season to taste. Do not allow the garlic to burn. Add around ¾ of the parsley (save the rest for a garnish).
Now add the water. Snap the spaghetti in half and layer into the pot. Press the spaghetti into the liquid, but do not stir.
Put the lid on and set on high pressure for 4 minutes. When the time is up leave for another 4 minutes and then do a quick release.
Remove the lid and separate any spaghetti that is stuck together using 2 forks. Stir in around ¾ of the parmesan (save the rest to garnish) and loosely put the lid back on until it has melted (this should take around 2 minutes)
Take the lid back off and serve garnished with the remaining parmesan and parsley.
Calories: 532kcal | Carbohydrates: 65g | Protein: 20g | Fat: 21g | Saturated Fat: 8g | Trans Fat: 1g | Cholesterol: 27mg | Sodium: 453mg | Potassium: 251mg | Fiber: 3g | Sugar: 3g | Vitamin A: 636IU | Vitamin C: 5mg | Calcium: 333mg | Iron: 2mg