There are a lot of have to’s for this. There is no way around it.
You have to buy the right spaghettone. It should be a little thicker than spaghetti and cut on an Italian bronze die. (Nobody else has mastered the bronze dies.) You have to buy parmigiano reggiano and pecorino romano from Italy. The romano made in the states is made from cow’s milk. No idea why they are allowed to call it a pecorino. Pecorino means sheep cheese. That is like serving someone a cup of tea and calling it coffee. Not right.
Finely grate each cheese. About 3/4 cup of grated cheese per person, and a one inch handful of pasta per person. Bring a pot of water to the boil and season the water with kosher or sea salt until it tastes delicious. Add the pasta and cook for 6 minutes.
In a heavy saute pan (cast iron or stainless) add freshly ground pepper over the surface of the pan-just whatever comes out of the mill as you move your way around the pan-not so that every millimeter of the surface of the pan is covered with pepper. Toast the pepper over a low flame, until you begin to smell it. Remove from the heat. When the pasta has reached 6 minutes, remove with a pair of tongs or a sieve, reserving the cooking water. Drop the pasta directly onto the pepper and turn the flame back on to about medium. Add one ladleful of cooking water and move the pasta around with pencil tongs. In a separate bowl, add about a half a ladleful of cooking water to your grated cheese. You are looking for a thick paste, just a tiny bit looser than library paste. Keep that on the side.
Continue to add cooking water to your pasta until it is al dente, and has a creamy liquid supporting it. You don’t want to cook it down to completely dry. When the pasta is al dente, add the paste in blobs around the surface of the pasta, and toss immediately with your pencil tongs to distribute the cheese. Check for looseness/creaminess. Add a few more drops of cooking water if you need to. It should have a beautiful emulsification. Plate and grate a bit more cheese over the top. Note: once you have the pasta in the pan with the pepper, it should take 4-5 minutes of cooking max. The al dente part is critical. You want the pasta to stand up in the sauce, not get absorbed by it. Who wants that?