For the beetroot purée, place all of the beetroot purée ingredients into a food processor and blend to a purée.
Transfer the purée into a frying pan over a low heat. Cook for 30-40 minutes, stirring occasionally. Season, to taste, with salt and freshly ground black pepper.
For the marinated beetroot, place all of the marinated beetroot ingredients into a bowl and season, to taste, with salt and freshly ground black pepper. Place into the fridge and leave for at least one hour, preferably longer.
For the pheasant, place the pheasant breasts onto a clean chopping board, cover with cling film, and tap gently with a rolling pin to flatten out slightly.
Season the pheasant breasts with salt and freshly ground black pepper, then dredge in the flour. Dip the floured breasts into the egg to coat, then dip into the breadcrumbs, coating thoroughly.
Heat a frying pan until hot, then add the butter and oil. When the butter has melted add the breaded pheasant breasts and fry for 1-2 minutes on each side, or until golden-brown all over and the pheasant is cooked through.
To serve, place a spoonful of beetroot purée into the centre of each plate. Cut the pheasant breasts in half lengthways and arrange two pieces onto each plate, balanced against the beetroot purée. Spoon the marinated beetroot around the pheasant and serve.