Hard-boil the egg, refresh in cold water, shell and reserve.
Put the shallots in a pan with the red wine vinegar, sugar and crushed black peppercorns. Cook over a moderate heat, until the vinegar has evaporated and the shallots are soft.
Add the chicken stock, bring to the boil and skim. Lower the heat and simmer for 10 minutes, then pass through a sieve into a clean pan.<