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Gooey chocolate chip cookie, gooey vanilla marshmallow, make THE most delicious s’mores cookie bars ever!

Ohhh so like.. yeah. Cookie bars happened again! I honestly couldn’t resist. I’ve actually baked these beauties several times, getting them slightly more perfect each time. I tried these in quite a few different ways, and honestly, this one stuck.

S’mores

How could you not love marshmallow and cookies together?! If you like s’mores then you will love these. Honestly… biscuit, marshmallow, and chocolate together is heaven. You can also try these guys warmed a little for ultimate s’mores experience.

My s’mores dip is slightly out of this world in my opinion, and I recently made my no-bake s’mores cheesecake again, along with my s’mores cake for a party and everyone said how good a cookie version would be… so I knew I should finally post this recipe.

So imagine a gooey, chocolatey cookie together with gooey marshmallow; my idea of heaven! These would suit being more towards Halloween and bonfire night, but I just couldn’t resist posting them now – it’s like marrying two of my favourite things together, s’mores and cookies.

Cookie bars

I went for my usual cookie bar style recipe, as I have also used in my Mini Egg cookie bars and Rolo cookie bars. These recipes are just utterly delicious, and since discovering what cookie bars all those years ago, I have been obsessed and more obsessed as time has gone on.

Butter – you can use either a baking spread, or an unsalted block butter at room temperature – both work well
Sugars – I classically use a mixture of white granulated sugar and light brown soft sugar because I like the flavour balance from both of them
Egg – I only ever use one egg, and I always buy medium, but one large would also work
Flavours – I love the addition of vanilla but this is optional
Flours – I use plain flour, as always, but I also add in some cornflour for texture
Raising agent – you only want to use bicarbonate of soda in these, which is nearly always needed in my cookie recipes
Salt – optional, but I adore a chunky sea salt added in for the balance of sweetness
Chocolate – you can use any you want, but I typically use milk or dark chocolate, or a mixture of both

Marshmallow

It’s hard to explain sometimes, but the marshmallow fluff makes the cookies gooier, and stops them drying out and just makes them utterly glorious. When I first wrote this recipe, and still often now if I am pressed for time, I use a shop bought marshmallow fluff because it’s just SO easy to use. It’s about 200g in the tub, and I slightly microwave the tub to soften the marshmallow and then scrape it out of the tub onto the cookie dough.

If you have a look at my s’mores cookie recipe however, you can see that I made my own version of marshmallow fluff for this, and it will work perfectly for these cookie bars as well – it’s a bit more intense to make your own, but it’s worth it if you are up for it.

Assembly

I love anything s’mores as I have said, but these are just DELIGHTFUL. You need to split the cookie dough into two sections… two thirds and one third.It can be a little bit faffy, but you need to press down the first lot of cookie dough so its even (often easier to use your hands) and then spread the marshmallow fluff on top.

The problem is, marshmallow fluff is so sticky, it’s easier to microwave it for 20 seconds so it’s spreadable! Then comes the problem of putting the next third of cookie dough on. I tend to pick the last third of cookie dough into small little pieces and then place it all over the top of the marshmallow so it spreads. You won’t be able to dollop it all on and spread with a spatula as it will just move all of the marshmallow out of the way.

Tips & Tricks

You can use any chocolate in the cookie bars, I just thought milk or dark chocolate would be a great fit for this recipe! I wouldn’t recommend using actual marshmallows for these though as they will just boil and disappear – nobody wants to look forward to these and them see no marshmallow goodness as the end of it – but you can make your own marshmallow fluff from my s’mores cookie recipe.

These cookie bars will last for 4-5+ days at room temperature
You can freeze these cookie bars for 3+ months
I use this 9×9″ square tin for this recipe