This is a creamy, cheesy, classic mac ‘n’ cheese! The macaroni cooks in vegetable or chicken broth, and there’s no straining or draining required. For a change of pace, switch out the Cheddar cheese for Fontina, Gruyère, or smoked Gouda.
Combine the macaroni, broth, and butter in the Instant Pot.
Secure the lid and set the Steam Release to Sealing. Select the Manual setting and set the cooking time for 6 minutes at high pressure. Perform a quick release by moving the Steam Release to Venting.
Open the pot and stir in the cheeses, sour cream, mustard, and cayenne pepper. Let sit for 5 minutes to thicken, then stir again and serve.