Vegetable stock
Slice and wash all vegetables, place in a large pan, add parsley, fennel seeds and anise. Just cover with water, bring to a boil and then simmer for 30 minutes. Store with the vegetables until required.
Onion stock
In a large frying pan cook the onions with a little olive oil, cut side down until almost black. Transfer to an oven at 170°C for 15 mins. Remove onions to a medium saucepan. Deglaze the frying pan with white wine and add to the onions with the thyme. Cover with cold water and simmer for 30 mins. Strain, pressing hard on the onions, and reduce to around 500ml.
Pasta sauce base
Combine the wines in a medium pan and reduce to a syrup, add the veg stock and reduce by 2/3. Add the onion stock and bring to a boil. This should be enough for around 10 portions.
Pasta dough
Sift the flour and salt into the bowl of a food processor. Whisk the egg and yolks with the olive oil.
Start the motor running on the processor and pour in the egg mix gradually. Scrape out all of the egg with a rubber spatula. Pulse the mix until a fine breadcrumb texture is achieved. Squeeze a small quantity of the dough together to check the consistency. You want a firm dough that is pliable and can be squashed between the fingers but is not overly soft or sticky. Tip the dough out onto a clean work surface, knead together and then oil lightly. Wrap in cling film and rest in the fridge for 30 min.
Fontina foam
Sweat the shallot and garlic in a drop of olive oil, add the wines and thyme. Reduce to a syrup and add the veg stock. Reduce by 1/3. Add the creme fraiche and mustard. Bring to a simmer and then pass into the Thermomix, blend in the grated cheese at 60°C, no 4, adjust the seasoning with Maldon salt and Dijon mustard.
Adjust the consistency to that of double cream by blending in small pinches of xanthan gum. Pour into a whipper gun and charge.
Roasted baby onions
Wash the onions and line a roasting tin with first foil and then silicone paper, allowing enough overlap to come over the top. Mix the salts with enough egg white to form a spreadable paste. Cover the bottom of the tin with half the salt mix and lay on the onions, scatter the thyme over. Cover with the remaining salt and seal up the parcel. Roast at 180-200°C for approximately 1 hour until the onions are soft when pierced. Break open the crust and allow to cool slightly before chilling.
For one starter portion
Sauté the onions in olive oil until starting to caramelise, add the garlic and cook until soft. Add the pasta sauce base and reduce by a quarter. Add a pinch of thyme leaves and then whisk in the butter and olive oil. Season. Cook the pappardelle and add to the sauce. Cook in the sauce for 1 min, adjusting the seasoning if necessary. Pile into a pasta bowl and top with some of the Fontina foam. Finish with a few thyme leaves and a drizzle of olive oil.