For the guinea fowl, place the chicken stock into a saucepan and add the guinea fowl, thyme and garlic. Bring to the boil then reduce the heat to simmer for about 15 minutes, or until the guinea fowl are completely cooked through.
Remove the guinea fowl from the cooking liquid and pat dry with kitchen paper. Remove the breasts from the carcass and set aside. (You can use the carcasses for another purpose, such as making stock.)
Heat a frying pan until hot, then add the butter and olive oil. Add the guinea fowl and pan-fry on each side until golden-brown on both sides. Remove and set aside in a warm place.
For the bubble and squeak, place the potatoes into a saucepan and cover with water. Add a little salt and bring to the boil, then reduce the heat and simmer for 15 minutes, or until cooked through.
Drain and return the cooked potatoes to the pan over a low heat to drive off any excess moisture. Mash the potatoes lightly and season with salt and freshly ground black pepper.
Meanwhile, place the Savoy cabbage into a heatproof bowl and cover with boiling water. Leave for 1-2 minutes, then drain and pat dry with kitchen paper.
Heat a frying pan until hot, then add the olive oil, potatoes and cabbage. Stir fry for 4-5 minutes, until crisp and golden all over. Season with salt and freshly ground black pepper and freshly grated nutmeg.
For the chipolatas, heat a clean frying pan until hot. Then add the butter, cocktail sausages and onions and cook for 1-2 minutes, until just starting to turn golden-brown.
Add the bacon lardons and thyme and cook for 4-5 minutes, until the lardons are golden-brown and the chipolatas are completely cooked through.
Add the sherry vinegar and stir to scrape up any cooking residue from the pan (this is called deglazing). Season with salt and freshly ground black pepper.
For the bread sauce, stud the onion with the cloves then place into a pan. Add the bay leaf and milk and place over a high heat. Bring to the boil, then remove from the heat and allow to cool.
Remove the onion and bay leaf from the milk and add the brioche crumbs. Place back onto a very low heat for 5-10 minutes, stirring occasionally until the brioche crumbs have absorbed all of the liquid.
Stir in the butter and season, to taste, with salt and freshly ground black pepper.
To serve, spoon some bubble and squeak onto each plate and top each with a guinea fowl breast. Spoon the chipolata mixture alongside, add a spoonful of bread sauce and serve.
