Heat a griddle pan over a high heat. Drizzle the oil all over the bread and toast on the griddle until golden-brown on both sides.
Heat a frying pan over a medium heat. Add the bacon and dry-fry until golden-brown and crisp. Remove from the pan using tongs and set aside on a warm plate.
Use the toast to soak up the bacon fat in the frying pan. Set the toast aside.
Return the frying pan to a medium heat, add the chicken livers and fry for 2-3 minutes, or until browned and caramelised.
Increase the heat and pour the brandy over the livers, scraping any burned bits from the base and sides of the pan with a wooden spoon to deglaze (CAUTION: Keep your face and hair away from the flames. Do not leave unattended.) .
Reduce the heat until the brandy is simmering. Add the cream, mangetout and sherry vinegar. Stir well and simmer for 1-2 minutes, or until the livers are cooked through. Season, to taste, with salt and freshly ground black pepper.
To serve, pile the rocket into serving bowls, then cut the toast into croûtons and sprinkle them over the rocket. Chop the bacon and sprinkle it on top. Spoon over the chicken livers and their sauce. Serve immediately.