A DAIRY mix-up has cost Mimi Baines her spot in MasterChef's quarter finals.

The Melbourne cook mistakenly thought she had goat's cheese, rather than ricotta, at her disposal in tonight's elimination challenge.

It was too late to change her dish and the production manager was left scrambling to adapt her dish to suit the ricotta.

"It was a bit silly," she told APN.

"When I found out I hadn't double checked the ingredients I had nothing else to go with."

Harry Foster's perfectly poached lobster and Elise Franciskovic's gooey chocolate brownie were too good for Ms Baines' disjointed dessert - fig ice cream with fresh figs and smoked ricotta.

The 26-year-old is now on the other side of the camera thanks to a job as a prep chef on a new TV show called My Market Kitchen hosted by former MasterChef winner Emma Dean and runner-up Lynton Tapp.

"I'm running around the Queen Victoria Markets grabbing ingredients for the show," she said.

"When I was on the MasterChef I thought that would be such a fun job to be on a food team.

"It's definitely a dream job."

Ms Baines is backing Elena Duggan and Elise Franciskovic for Tuesday's grand final, rather than Matt Sinclair or Harry Foster.

"I really want the girls to do well," she said.

"They're both so talented and underestimated."

MasterChef's final masterclass for the year airs tomorrow night and then the Top 4 face off in the quarter finals on Sunday night.