Step 1

Pour the broth into the Instant Pot, break the spaghetti over it and add to the broth, then follow with 4 tablespoons of the butter.

Step 2

Secure the lid and move the valve to the sealing position. Hit Manual or Pressure Cook on High Pressure for 8 minutes. Quick release when done. (NOTE: The pasta will appear soupy once the lid comes off. This is what we want because adding the dairy will thicken it up perfectly.)

Step 3

Stir in the remaining 4 tablespoons butter until melted, then add the cheese and stir until well combined. The sauce will thicken as soon as the cheese is absorbed, which is almost immediately.

Step 4

Add the cracked black pepper and give it a final stir. Add more pepper to taste.

Step 5

Transfer the pasta to bowls and top with more cheese and pepper, if desired.