  The Mpemba effect describes the situation in which a hot system cools faster
than an identical copy that is initiated at a colder temperature. In many of
the experimental observations of the effect, e.g. in water and clathrate
hydrates, it is defined by the phase transition timing. However, none of the
theoretical investigations so far considered the timing of the phase
transition, and most of the abstract models used to explore the Mpemba effect
do not have a phase transition. We use the phenomenological Landau theory for
phase transitions to identify the second order phase transition time, and
demonstrate with a concrete example that a Mpemba effect can exist in such
models.
