Cook the bucatini in a large pot of salted water according to package instructions until al dente.
While the pasta cooks, grate the white cheddar and set aside. Tip: chilling the cheese for 10–15 minutes in the freezer makes grating easier.
Once the pasta is cooked, drain it but do not rinse. Return the empty pot to the stovetop (with the burner turned off) and immediately add the drained pasta back in.
Sprinkle in the black pepper, then stir in the grated cheese, mayonnaise, and warmed evaporated milk. Mix thoroughly to melt the cheese and create a creamy sauce.
Add pepper sauce if desired and mix well. Taste and adjust salt to your preference. You may substitute butter for mayonnaise if preferred.
Serve immediately. Enjoy plain or topped with your favorite stew gravy or even a few drops of ketchup or sliced boiled eggs, island-style.