Chloe Carroll

The contestants are given 60 minutes to make a dish with one loaf of bread as the mystery box ingredient. Plus, a reinvention test involves spaghetti bolognese ingredients.

The contestants have to follow 90 steps of a recipe to replicate a marron dish by Ashley Palmer-Watts in four hours and 45 minutes.

The contestants face an offsite challenge in Melbourne's inner city suburb of Fitzroy, where they must each prepare a main course and dessert for 25 people.

It is the first mystery box challenge, with one contestant choosing eight ingredients for chefs to cook from and make a dish in 75 minutes.

On the first day of finals week, each contestant has to cook a mystery box that featured in a previous season of the show.

The contestants have to reinvent three humble frozen dinners, including fish and chips, a chicken dish and beef with three types of vegetables.