purrfectlydevine
Sous Chef
Just a thought--perhaps by keeping it in the pot to refrigerate, the filling is in the danger zone (temperature) too long and is spoiling because of that. By putting the filling is several smaller containers you increase the surface to mass ratio (where have I heard that before?) and speed cooling. You could also fill a larger pan with ice and put your filled containers in that to speed cooling, but that has been said.