Wash the black kale, remove the tough stems, and tear the leaves into bite-size pieces.

Grate the Pecorino Romano cheese finely and set it aside for the pasta cream.

Remove the scallop coral if present, then pat the 4 scallops completely dry.

Cut the guanciale into thin strips, then dice the strips into small cubes.

Bring 4 l of water to a boil on the stovetop and season it with 1 tbsp salt.

Heat a dry frying pan over medium heat and cook the diced guanciale until its fat renders and it becomes crisp, about 5 to 7 minutes.

Transfer the crispy guanciale to a plate with a slotted spoon, leaving a little rendered fat in the frying pan.

Melt 15 g salted butter in a second hot frying pan, then add the 4 dry scallops.

Sear the scallops for 1 to 2 minutes per side until deeply golden while keeping their centers tender.

Add the spaghetti to the boiling salted water and cook it for 2 minutes less than the package instructions.

Reserve 240 ml of starchy pasta water, then transfer the undercooked spaghetti to the pan containing guanciale fat.

Add the black kale and 120 ml reserved pasta water, then toss over medium heat until the kale wilts and the spaghetti finishes cooking.

Remove the pan from the heat and add the grated Pecorino Romano cheese with black pepper.

Toss the pasta vigorously, adding the remaining reserved pasta water a little at a time until a glossy Pecorino cream coats the spaghetti.

Divide the creamy pasta among 4 plates and scatter the crispy guanciale over each portion.

Top each serving with one seared scallop and serve immediately while the cheese sauce is creamy.