Episode 1: Cake

For the signature challenge, the bakers created an intricate Battenberg cake in 2 hours. The technical challenge set by Paul gave the bakers 90 minutes to bake 6 miniature pineapple upside-down cakes. At the end of the challenge, Sura, who saw a fly and was trying to brush it away, accidentally hit Dave's tray of 6 miniature cakes as he was setting them down, knocking 4 to the floor. Prue and Paul judged the better looking of the remaining two, assuming the rest were the same. In the showstopper challenge, the bakers created a 3-D cake bust depicting their personal celebrity hero, in 4 hours.

The broadcast of Episode 1 began at 8:15pm instead of 8:00pm, following Prime Minister Boris Johnson's address to the nation on the COVID-19 pandemic. The episode began with a parody of the Johnson address by new presenter Matt Lucas.^[22]

Episode 2: Biscuits

For the signature challenge, the bakers were tasked with making 36 identical chocolate florentines, in 2 hours. The technical challenge, set by Prue, required the bakers to make 12 hand-shaped coconut macaroons, six piped with a mango curd and the other six drizzled and filled with chocolate, in 1 hour and 45 minutes. For the showstopper challenge, the bakers were given 4 hours to create a beautiful molded 3D biscuit table setting representing a memorable meal they had in the past.

Episode 3: Bread

The signature challenge tasked the bakers with making 2 freeform soda bread loaves, one savoury and one sweet, and an accompanying butter in 1 hour 45 minutes. The technical challenge, set by Paul, tasked the bakers with making 6 rainbow-coloured bagels in honour of the NHS, in 2 hours 45 minutes. For the showstopper challenge, the bakers were asked to create a large decorative bread plaque in the style of a traditional harvest festival sheaf, portraying the one thing in life they are most grateful for, in 3 hours 30 minutes.

Episode 4: Chocolate

The signature challenge was back to basics as the bakers were asked to make 18 chocolate brownies, in1 hour 30 minutes. For the technical, Paul tasked the bakers with making a traditional Jewish bake: chocolate Babka, in 2¹⁄₂ hours. In the showstopper challenge, the bakers were required to produce a spectacular two-tiered white chocolate celebration cake in 4 hours.

Episode 5: Pastry

For the signature, the bakers were tasked with putting their own spin on Cornwall's national dish: the pasty, in 2 hours. The technical challenge, set by Prue, required the bakers to make 6 éclairs; three raspberry, and three salted caramel, in 2 hours 15 minutes. For the showstopper, the bakers were given the intricate task of making a sweet tart hidden under a latticed pastry cage, in 3 hours 45 minutes.

Episode 6: Japanese

Week 6 was a Bake Off first as the bakers tackled Japanese week. The signature challenge tasked the bakers with making 8 steamed buns, complete with a savoury or sweet filling and decoration, in 2 hours 30 minutes. For the technical challenge, Prue asked the bakers to make a Matcha Crepe Cake consisting of 12 layers of crepes sandwiched with a white chocolate ganache buttercream and strawberries, decorated with fresh fruits and edible flowers on top, in 2 hours. The showstopper gave the bakers 4 hours to produce a cake inspired by the kawaii culture in Japan, incorporating Japanese flavours.

This was the 100th episode of the Great British Bake Off throughout all seasons.

Episode 7: The '80s

For the signature challenge, the bakers were asked to perform their own twist on 8 classical quiches with two different styles in 2 hours. For the technical challenge, Paul asked the bakers to make 6 deep-fried, identical custard & jam finger doughnuts in 2 hours 45 minutes. For the showstopper challenge, the bakers were required to make an ice cream cake, which was considerably more difficult since it was the hottest day of the year, in 4 hours 30 minutes.

Episode 8: Desserts (Quarterfinals)

The signature challenge tasked the bakers with making 12 mini baked cheesecakes, in 2¹⁄₂ hours. For the technical challenge, Prue set a 17th-century bake: 2 Sussex pond puddings using suet pastry and served with creme anglaise, again in 2¹⁄₂ hours. For the showstopper challenge, the bakers were given the enormous task of making a jelly art design cake, composed of an artistic jelly design, a mousse and a baked sponge element in 4¹⁄₂ hours.

Episode 9: Pâtisserie (Semifinals)

The signature challenge required the bakers to make 12 Pâte à Savarin in 2 hours 45 minutes. The penultimate technical challenge, set by Paul, gave the bakers the challenging task of making a Danish Cornucopia cake, kransekage, in 2 hours 15 minutes. For the showstopper challenge, the bakers were given 4¹⁄₂ hours to make 25 cube-shaped cakes that required the precision expected in pâtisseries.

Episode 10: Final

For the final signature challenge, the finalists were tasked with making 8 beautifully decorated custard slices, in 2¹⁄₂ hours. For the final technical challenge, Prue asked the bakers to make 8 identical walnut whirls — a cone of chocolate with marshmallow inside, a biscuit base, and topped with walnuts, in 2 hours. For the final showstopper challenge, the bakers were tasked with making a colossal, spectacular dessert tower with a large cake at the base and at least 3 sections to represent the different baking disciplines, in 4¹⁄₂ hours.

The judges said this was the closest final in the history of the show. Peter is the youngest ever winner of the Great British Bake Off.

The Great Christmas Bake Off

The Great Christmas Bake Off features James Hillery from Series 8, Ruby Bhogal from Series 9, Jamie Finn and Rosie Brandreth-Poynter both from Series 10. An Extra Slice presenter Tom Allen took over Noel Fielding as co-host with Matt Lucas, as Fielding welcomed the birth of his second child prior to filming and was on paternity leave.

For the signature challenge, the bakers were given three hours to create 12 miniature panettones. Prue's technical challenge required the bakers to make a quick Christmas pudding (with mincemeat made from scratch), to be cooked in a microwave and served with a Crème anglaise, in one hour and 15 minutes. The showstopper challenge asked the bakers to make an illusion cake to depict their ultimate Christmas day feast, in four hours.

The Great New Year Bake Off

The Great New Year Bake Off featured Helena Garcia and Henry Bird from Series 10 as well as Series 5 winner Nancy Birtwhistle and Series 9 winner Rahul Mandal, making it the first time in the show's history two former winners were featured competing against each other. Noel Fielding returned to host alongside Matt Lucas.

The signature challenge required the bakers to make a fruit crumble, served with a complementary ice cream, in two hours. Paul's technical challenge tasked the bakers with making 6 steamed bao buns with shredded crispy duck fillings, in two hours. To celebrate the 2021 New Year, the bakers were asked to make a cake celebrating their 21st birthday for the showstopper challenge, in four hours.