Place the elbow macaroni into a 6- or 8-quart Instant Pot® multi-cooker, accompanied by 4 cups of water and 1 tablespoon of kosher salt. Secure the lid as per the manufacturer's instructions and set the device to pressure cook on high for 4 minutes.

Once the cooking cycle concludes, refer to the manufacturer’s guide to perform a quick release of pressure. Once all steam has dissipated, carefully unlock and remove the lid. Switch the device to the low sauté setting for the next step.

Gradually stir in the evaporated milk, butter, and ¼ cup of water. Slowly incorporate the shredded Cheddar cheese, stirring consistently until all the cheese has melted and the mixture is smooth. Serve the dish immediately, while hot.