Preheat the oven to 200°C / 400°F and spread the coarse salt in the baking dish.

Place the 1 kg potatoes on the salt bed and bake until fully tender, about 60 to 90 minutes depending on their size.

Cut the hot potatoes open and press their flesh through the potato ricer into the large mixing bowl.

Add the egg and 250 g wheat flour to the warm riced potatoes.

Mix while warm, then knead just until a smooth and homogeneous dough forms.

Divide the dough into portions and roll each portion into a long rope about 2 cm thick.

Cut the ropes into bite-size gnocchi pieces and mark each piece with the fork if desired.

Put the 250 g guanciale lardons in the large frying pan and cook over low heat until crisp.

Remove the crisp guanciale with the slotted spoon and discard most of the rendered fat, leaving a thin coating in the pan.

Crush the 800 g peeled tomatoes directly into the pan and season with the fine salt and half of the black pepper.

Simmer the tomato sauce very gently for about 20 minutes, stirring occasionally.

Bring a large pot of salted water to a boil and cook the gnocchi in batches until they float, about 2 to 3 minutes.

Transfer the cooked gnocchi to the tomato sauce and toss gently to coat.

Add about half of the Pecorino Romano cheese and toss until it lightly melts into the sauce.

Plate the gnocchi and top with the crisp guanciale.

Finish each plate with the remaining grated Pecorino Romano cheese and black pepper.