*This post may contain affiliate links. Please see my disclosure for more details!*

A giant chocolate chip cookie perfect for birthdays! Who doesn’t want a giant birthday cookie?! 

Giant birthday cookie

So it’s 2021 now… and I thought it was about time that I posted one of the most highly requested recipes EVER. A giant birthday cookie. I can’t honestly blame you all for wanting one… who doesn’t want a giant cookie for their birthday if they like cookies?! 

This beauty of a recipe is very heavily based on my cookie bar recipes, such as my mini egg cookie bars, and my kinder bueno cookie bars. The base recipe is so good, and it works so well every time I didn’t want to mess with it to be honest!

Dough

This recipe is also inspired by my mini egg cookie cake, and my triple chocolate cookie cake. I use those as inspiration as the baking times when baking into a round tin can vary quite a bit in comparison to a square tin, and you know… birthday cake! 

So, I decided as everyone asks for a Millie’s inspired giant cookie, that I would go down the idea of a plain/vanilla cookie base, with chocolate chips inside. This is just because it’s the best base to start with, and you can SO easily swap it about and customise it to what you prefer! 

Butter, sugar, flour and cornflour

For the base recipe, you can use real butter or a baking spread, but I do recommend using the two types of sugars, and the correct two types of sugars. They are there for a reason!I use plain flour because you don’t want the raising agent from self raising flour. 

I also use cornflour – this is because it creates SUCH A GOOD TEXTURE. Please do not just skip it. If you can’t access any cornflour/cornstarch, then use 25g more plain flour instead! Please also make sure to use bicarbonate of soda/baking soda… and not baking powder. 

Chocolate

I used a mixture of white and milk chocolate chips, but you can use any. You can use chocolate chips, chunks of a chocolate bar, milk, plain or white… or flavour chocolate such as terry’s chocolate orange, or Lindt for example! You can also use themed chocolate such as Mini Eggs! 

I recommend sticking to a maximum of 400g of added chocolate because as you can see from the photo… it’s pretty full. The smallest amount I would say is 200g, otherwise it may become a little dry without any chocolate in there! Also, more chocolate the better in my opinion. 

Size/Tin

I decided to bake this giant birthday cookie into an 8″/20cm round cake tin, because that is a standard cake size for me! It takes 25-30 minutes to bake – and you want to keep an eye on it. You wan’t the top of the cookie to look dry, but you also do not want the mixture to wobble too much as it may be raw still! 

If you want a large but thinner cookie, you can use a 9″/23cm round cake tin, and bake for 20-25 minutes instead, and follow the same rules as above! It’s easier to line the tin so that you can easily get the cookie out of the tin after, without breaking it into pieces! 

Topping

For the topping, I just made a simple vanilla buttercream (you don’t need much as it’s only a cookie!) – and you can colour it to any colour you like!! I then used some shopbought letters for the ‘happy birthday’ and sprinkled on some cute sprinkles from Iced Jems as always! 

You can adapt this cookie for any occasion, not just birthdays! But I have a similar version for Christmas and Valentines, and even a Mini Egg cookie cake for Easter – YUM!

Giant Birthday Cookie!

A giant chocolate chip cookie perfect for birthdays! Who doesn't want a giant birthday cookie?! 
Print Pin Rate
Category: Cake
Type: Cookies
Keyword: Cookie Cake, Cookies
Prep Time: 10 minutes
Cook Time: 25 minutes
Cooling & Decorating: 2 hours
Total Time: 2 hours 35 minutes
Servings: 10 Slices
Author: Jane's Patisserie

Ingredients

Cookie Cake

  • 275 g plain flour
  • 1 tsp bicarbonate of soda
  • 1/2 tsp salt
  • 1 tbsp cornflour
  • 115 g unsalted butter
  • 55 g white granulated sugar
  • 135 g light brown soft sugar
  • 1 medium/large egg
  • 1 tsp vanilla extract
  • 100-200 g milk chocolate chips/chunks
  • 100-200 g white chocolate chips/chunks

Buttercream

  • 75 g unsalted butter (room temp)
  • 150 g icing sugar
  • 1/2 tsp vanilla extract

Decoration

  • Sprinkles/candles/letters/etc

Instructions

  • Preheat your oven to 190ºC/170ºC fan and line a 8"/20cm round tin with parchment paper, and leave to the side for now.
  • Whisk/mix the plain flour, bicarbonate, salt and cornflour together so its evenly distributed – leave to the side.
  • In a larger bowl, melt the butter. Add in the two sugars, and whisk for about 2 minutes so the sugar starts to dissolve and the mixture is smooth. Add in the egg and the vanilla, and whisk again briefly until smooth.
  • Add in the dry ingredients, and the chocolate chips (apart from a small handful) and mix with a spatula or a mixer until a thick cookie dough is formed.
  • Press the mixture into the bottom of the tin and press in the handful of chocolate chips into the top for decoration.
  • Bake the cookie in the oven for 25-30 minutes, until the top of the cookie looks ‘dry’ and it's not wobbling!
  • Leave the cookie to cool in the tin fully.
  • Once the cookie has cooled, beat the unsalted butter for a minute or two to loosen and soften.
  • Add the icing sugar and vanilla extract and beat again until smooth.
  • Pipe around the edge of the cookie however you want, and add any to the middle if you want.
  • I then used some shopbought edible happy birthday letters, and some sprinkles!

Notes

  • This cookie will be best eaten on the day of baking or the day after, but will last 4-5 days.
  • You can use any chocolate chip or chopped chocolate you want in the cookie - stick to a minimum of 200g, and a maximum of 400g. 
  • If baking into 9"/23cm tin for a thinner but larger cookie, bake for 20-25 minutes. 
  • If you can't access cornflour - use 25g more flour, but the texture will change. 
  • You can make the cookie chocolate themed by using 200g plain flour, and 50g cocoa powder. 
  • I use this 8" cake tin, or this 9" cake tin
  • These are the edible letters I used
  • These are the sprinkles I used

ENJOY!

Find my other Cookie & Cookie Bar Recipes on my Recipes Page!

You can find me on:
Instagram
Facebook
Pinterest
Twitter
Youtube

J x

© Jane’s Patisserie. All images & content are copyright protected. Do not use my images without prior permission. If you want to republish this recipe, please re-write the recipe in your own words and credit me, or link back to this post for the recipe.

253 Comments

  1. Emma on October 18, 2025 at 12:09 pm

    My children have this recipe every birthday instead of a cake and we use mini eggs to make it for Easter too.
    It has never failed to impress.

  2. Karen Forrester on April 28, 2025 at 11:01 pm

    Hi I have been asked to make this as a traybake (9” x 13”) how much would you suggest I increase the recipe by please? Thank you.

  3. Leighann on November 26, 2024 at 2:37 pm

    Can i make the dough up and freeze it you use at another time?

  4. Frances on October 16, 2024 at 9:37 pm

    My cake fell through the bars of my wire rack ! 🙁 I left it to cool in the tin for 10 mins . Do people tend to leave it longer ?

    • Jane's Patisserie on November 22, 2024 at 3:31 pm

      Oh no!! Leave it in the tin to cool fully x



  5. Donna on September 21, 2024 at 8:37 pm

    5 stars
    I have made this cookie multiple times now and it is always delicious! All my neices and nephews request it instead of birthday cake!

    My boyfriend has requested a “caramel and white chocolate” version of it. Any idea how best to incorporate caramel flavour in??

    Thanks!

  6. Julie on September 15, 2024 at 3:53 pm

    5 stars
    Hi Jane, thinking of making this for my husband’s birthday but as a white chocolate macadamia version..would I just adapt the cookie recipe or do you have any recommendations for quantities?! Many thanks in advance 🙂

  7. Sarah B on May 10, 2024 at 4:14 pm

    Absolutely love baking this, done it more times than I can remember and it always goes down a storm — thank you !!

    Any idea how long I would bake it for if I was to use a 6″ tin and split the mixture between 2 of them? Thanks in advance 🫶

    • Julie on September 14, 2024 at 4:37 pm

      Hey 🙂
      Would it be possible to make this as a giant white chocolate macadamia cookie? I’m not too sure what quantities would be needed of nut to chocolate?!



  8. Pippa cook on April 25, 2024 at 9:46 pm

    Hi , how much mix would I need for a 28cm backing tin as would like to make a large thinner cookie. I was thinking a batch and a half .would this be enough ?

  9. Rhi on December 10, 2023 at 12:07 pm

    Hi can I make and bake the Cookie in advance and freeze, ready to decorate at a later date?

Leave a Comment

Recipe Rating








This site uses Akismet to reduce spam. Learn how your comment data is processed.