Gregg Wallace is in Stoke-on-Trent at an enormous cherry bakewell factory where they produce 250,000 little tarts every day. He follows the production of cherry bakewells, from the arrival of 27 tonnes of flour right through to dispatch. Along the way, he learns what makes a shortcrust pastry ‘short' and discovers the simple way they ensure every cherry is precisely placed. They employ a team of 12 who carefully pop each one on top by hand.

Meanwhile, Cherry Healey is learning how to swerve a soggy pastry bottom when baking pies and tarts at home. She discovers that it is all about a pre-heated oven, a proper pie dish, rolling the pastry to the correct thickness and blind baking. And she is at an almond butter factory, learning how almonds are roasted and milled to become a thick spread ready for toast.

Historian Ruth Goodman is sniffing out the origins of one of the cherry bakewell's key ingredients, frangipane. She learns that, surprisingly, the familiar fragrant almond filling was born out of a perfume used to disguise the foul smells of 17th-century Paris. She also visits the Peak District town of Bakewell and learns how the modern cherry bakewell is a descendent of a simple recipe mistake in the kitchen.

Gregg Wallace is in France at an enormous croissant factory where they produce 336,000 of the flaky pastries every day. He follows the production of croissants from the arrival of 21 tonnes of butter right through to dispatch. Along the way he learns how they use an 83-year-old strain of yeast to pack a flavourful punch and discovers the secret of pastry lamination. They layer very thin slices of butter between sheets of dough to create the famous flaky pastry.

Meanwhile, Cherry Healey is testing the best way to eat a croissant. With the help of a professor who specialises in the science of our senses, she discovers that there is an optimum way to consume them. Ideally, they will be served warm so that the butter inside oozes fat into the pastry, smothered in jam to give a sugar and fat hit, and eaten from a paper bag so that the crinkly sound accentuates the flaky texture of the pastry. She also heads to north Wales, visiting a farm and dairy where they produce a special type of ‘concentrated' butter. The butter is a whopping 99.8% fat, perfect for producing croissants with a long shelf life.

Historian Ruth Goodman is in Paris investigating the croissant's surprising Austrian origins. It is thought that it originated with a pastry called a kipferl, which Austrian bakers invented in the 17th century to commemorate a heroic victory over the armies of the Ottoman Empire. Its shape was a mocking reference to the crescent on their enemy's flag. But it took a while to transform into the modern pastry - the earliest written recipe she manages to find for a modern French croissant comes as late as 1906. Ruth also discovers that bread played a vital role in the French Revolution.