Add macaroni, salt and water to a 6 or 8 quart Instant Pot. Set the pressure valve to sealing. Cook on high pressure for 4 minutes. Once done, carefully move the valve to release the pressure.
Stir the pasta. Add in the remainder of the ingredients and mix until fully combined. If pasta is too thick, add a bit more milk in. Taste and add additional salt and pepper, if desired.
Garnish with additional parmesan cheese and serve immediately.
Freshly shredded cheese works best here, as pre-shredded cheese can have added stabilizers and won’t melt as well.
If you have an Instant Pot model that includes an air fryer you can add additional cheese to the top and swap the lids to broil for 4 minutes to get a nice crispy lid.
If pasta has excessive liquid, drain some of it. There should be some liquid left, but the pasta shouldn't be swimming in it. We have noticed that some brands or shapes of pasta leave more water than others. See note in body of post for more info.