Combine macaroni, chicken stock, salt, dry mustard, liquid smoke, paprika, pepper, and garlic powder in a multi-functional pressure cooker (such as Instant Pot(R)). Close and lock the lid. Select high pressure according to manufacturer's instructions; set timer for 4 minutes. Allow 10 to 15 minutes for pressure to build.
Release pressure carefully using the quick-release method according to manufacturer's instructions, about 5 minutes. Unlock and remove the lid. Stir in butter, milk, Cheddar cheese, and Parmesan cheese until melted. Mixture will be soupy at first.
Select the "Keep Warm" setting on the Instant Pot(R) and allow macaroni to sit, uncovered and stirring occasionally, until all liquid has been absorbed and consistency is smooth and creamy, about 15 minutes.
