Place macaroni, chicken stock, milk, butter, mustard, paprika, garlic and salt (if using) in the inner pot and mix well.

Cook in Instant Pot on Manual (your Instant Pot button might say Pressure Cook instead of Manual) for 5 minutes, high pressure, wait a few seconds for things to settle down inside and do a quick release (in conventional pressure cooker: 5 minutes on high pressure once it starts whistling followed by a quick release). The wait is because pasta foams up and it can splatter when you quick release, believe it or not cheaper supermarket-own brands are better for pressure cooking so save your pennies. Some people place a tea towel over the lid just in case it splatters when quick releasing pasta just in case it splatters but this is NOT a recommended practice, I tend to let it settle down inside first, 30 seconds-one minute. The other thing you can do is a gradual quick release, start letting the steam out after the resting time, if it splatters then close the vent again, then try again after a little while. Another trick is to cook it for 4 minutes and let it have about 3-4 minutes natural release, way less splatter that way too. This applies to any pasta dishes you cook in your Instant Pot.

When finished: mix in grated cheese, grated Parmesan, and cream cheese until all combined! Let it sit for a couple of minutes. Serve immediately.