Heat a couple of knobs of the butter in a frying pan, season the livers and fry them on a high heat for a minute, turning them as they are cooking to keep them nice and pink. Remove them from the pan and transfer to a plate. Add the shallots to the pan and fry on a low heat for a minute, then add the sherry and simmer for 20 second. Next add the parsley and cream and reduce by half until thickened, then add the livers and remove from the heat.
To make the omelettes, heat a little butter in a non-stick frying pan and add a quarter of the beaten eggs, stir on a low heat with a wooden spoon or spatula until the egg begins to set, then stop stirring and allow the egg to just set on the bottom of the pan. Remove the pan from the heat and fold both ends towards the middle then roll the omelette out onto a warmed serving plate. You can shape the omelette into a cigar with a clean tea towel or with your hands. Keep warm in a very low oven whilst you make the others or just reheat them briefly once they are all cooked.