Stir Elbow Macaroni (16 ounce), Butter (2 tablespoon), Yellow Mustard (1 tablespoon), Hot Sauce (1 teaspoon), Salt (1 tablespoon), and Water (4 cup) in the Instant Pot. Lock the lid and cook on high pressure for 4 minutes. Quick release the pressure and remove lid.
Turn on Sauté Setting. Stir in the Evaporated Milk (12 fluid ounce). Add Sharp Cheddar Cheese (16 ounce) and Parmigiano-Reggiano (6 ounce) one handful at a time, stirring constantly allowing cheese to melt between each handful.
Remove from heat. Set for 2 minutes for the milk and cheese to completely absorb the pasta and serve!