For the dough, rinse the potatoes, remove the skin and cut into quarters. Cook in a little salted water.
Drain the cooking water, press the potatoes through a potato press and steam. Stir in the egg, mascarpone, semolina and pine nuts, season with salt, pepper and nutmeg and knead until smooth.
Fill the potato mixture into a large piping bag with a large nozzle, pipe finger-thick rolls onto a floured surface and cut them into 2-3 cm long pieces.
For the sauce, boil the clear soup, whipping cream, vinegar and sherry by 1/3 in a sauté pan or possibly a high-walled saucepan.
In a large pot, bring enough salted water to a boil.
Cook the gnocchi in the salted water. As soon as they float to the surface, lift them out with a slotted spoon and fry them in the heated olive oil until they are well drained. Season with salt and pepper.
Finally, finely chop the basil leaves and fold into the thickened sauce with the whipped cream.
Divide the gnocchi evenly on preheated plates, pour the sauce over them and bring to the table sprinkled with the grated cheese.
Using a piping bag, pipe the potato mixture onto a floured work surface in finger-thick rolls and cut into 2-3 cm long pieces.