The teams face testing challenges judged by world-class patisserie experts Benoit Blin and Cherish Finden.
In this episode, hosts Liam and Tom welcome back the four remaining teams to take on the edible beast that is chocolate week.
For Benoit and Cherish, nothing less than perfection will do and they have a surprise up their sleeves in the shape of a secret challenge, where the teams must hero both chocolate and one of Benoit's favourite ingredients... without any recipes to hand.
Who will rise and who will fall at this first chocolate challenge? For the showpiece challenge, the teams must construct tall, beautiful and technically-precise mechanical chocolate showpieces, along with 48 chocolate bons bons with a moving part, inspired by the theme of robots... all in five hours. Which three teams will march on into the next round?
Bake Off: The Professionals continues Tuesday at 8pm on Channel 4.