Bake the potatoes at 200°C to a core temp of 98°C. Scoop out the potato with a spoon and keep the skins for the broth. Pass the potato mass through a fine sieve. Grate the cheese. Combine all ingredients and season with salt. Transfer the mass to a piping bag.
Roll out the dough using a pasta roller (steps 7-1). Cut the dough into squares, and pipe the filling onto the pasta sheets. Roll into agnolotti – cylinders and press the ends to close.
Before serving: Boil the agnolotti for 2 minutes. Fry sage and garlic in the butter and add a few spoonfuls of pasta water. Toss the pasta in the butter.
Bake the eggs for 1h in a circulator at 67°C. Take out the yolks (keep the whites for the foam). Whisk the yolks and season with salt. Smoke the cream with a smoking gun, transfer it to a piping bag and keep it cold. If you don’t have access to a circulator, you can boil your eggs for about 6 minutes instead, and if you don’t have access to a smoking gun, the cream does not need to be smoked.
Brown the butter and pluck the herbs. Let the herbs infuse 5 minutes in the butter. Mix in a blender and strain the mixture. Run the butter in the blender with the whole egg and the eggwhites. Season with salt and Champagne vinegar. Pour the cream into a siphon and load it with 2 gas cartridges. Cook in a water bath at 60°C. If you don’t have access to a siphon, you can leave out the eggs and serve the butter as a sauce.
Vacuum seal the potato skins with water and salt. Steam 30 minutes at 100°C. Strain the broth and reduce it. Serve it in a jar with herbs and potato skins as garnish. If you don’t have access to a steam oven you can simmer the broth in a saucepan for the same amount of time.
Peel and wash the potato. Rinse it to remove the starch and leave it a few minutes in water. Dry the potato with paper and deep fry it in batches. Drain on paper.
Pluck and fry the leaves of the sage. Drain on paper. Pluck the chervil and place in cold water. Before serving, grate the cheese over the plates.