The 40-year-old model and the 59-year-old former Countdown presenter were the latest stars to compete in the Channel 4 celebrity baking show, alongside reality TV judge Rob Rinder and stand-up comedian Mo Gilligan.
Brook and Vorderman both chose to bake cakes in the shape of themselves in a bubble bath for their ‘Guilty Pleasure’ inspired Showstopper Challenge.
The two former winners of Rear of the Year had viewers bubbling over with excitement as they described themselves soaking naked in the bath.
Brook attempted to bake a sponge infused with pink champagne - but it ended up too soggy. So Vorderman championed with her strawberry and chocolate cake, covered with white fondant icing which she poured fresh fizz into for judges Paul Hollywood and Prue Leith to drink from a straw.
Read more: Kelly Brook's muffins are a Hollywood hit
After being awarded the Star Baker apron, Vorderman gasped: “No way. I am genuinely shocked. I’m chuffed. Seeing as nobody expected me to bake a cake again.”
Brook laughed: “Let’s be honest no one was ever going to beat Carol. She can fly a plane for goodness sake.”
Hollywood said: “Carol was always going to be Star Baker. But Kelly was a close second.”
Brook left Hollywood and host Noel Fielding blushing as she created the image of her ideal bubble bath scenario.
She said: “My guilty pleasure is to spend a day out in my garden. Then I decide to strip off and have a lovely bubble bath with pink champagne. I have dirty knees because I’ve been out there all day on my hands and knees.”
Criminal barrister and reality TV star Rinder, 41, revealed his guilty pleasure was to read trashy romantic fiction.
He cheekily told Hollywood, 54,: “You have a Jackie Collins male lead-esque quality to you I think.”
Judge Leith told Rinder of his cake: “The theme is trashy novels and it looks like trash.”
But she went on: “That is a beautiful tasting cake. You are a natural cake baker, but hopeless decorator.”
Comedian Gilligan attempted to make trainer-shaped cake – admitting he can buy up to eight pairs of trainers a month. It was flavoured with peanut butter and raspberry jam.
Hollywood said: “It does look like a train as supposed to a trainer... It looks hideous but tastes amazing.”
For the initial rounds the celebrities baked biscuits - with Brook winning praise for egg muffin breakfast biscuits. They also attempted to make cream-filled ice buns in the Technical Challenge. Vorderman was placed first, while Brook came third for making her buns round instead of long.
The celebrity spin-off of the hit baking show in aid of Stand Up To Cancer this year saw stars including Jaws star Richard Dreyfuss, documentary maker Louis Theroux, EastEnders actress Patsy Palmer and singer James Blunt among those taking part.