Abstract: A single bladed cooking knife having two aligned cutting edges. An enclosure for the knife is provided in which an upper half-shell are joined and a lower half-shell joined to each other to form an enclosure for the knife; one end of the knife is coupled to the enclosure for pivoting the knife from a first position within the enclosure with one of the cutting edges positioned within the enclosure and another of the cutting edges being external of the enclosure to a second position with both of the cutting edges external of the enclosure. The knife blade is lockable, in the first and said second positions, and the knife blade is associated with a mechanism for unlocking the knife blade to move the knife blade from the first position to the second position and vice-versa.