Split lamb kidneys in half and fasten open with toothpicks. Cook in a frying-pan thin slices of fat breakfast bacon until clear, but not crisped. Take up and keep hot while you cook the kidneys in the bacon-fat, turning them frequently. Six minutes should make them tender. Long cooking toughens them. Arrange upon thin slices of toast in a dish, garnish with the bacon, add a teaspoonful of Worcestershire sauce to the gravy and pour over the kidneys.