The ultimate homemade chocolate bar? Crumbly oat biscuit, topped with crunchy puffed rice in chewy marshmallow and encased in milk chocolate – I’d say these oat and marshmallow crispy bars are a strong contender.
My Signature Chocolate Biscuit Bar
As some of you know I love to watch the Great British Bake Off and then make and post a recipe inspired by the show.
I usually opt to do one of the signature bakes or the technical challenge. For biscuit week 2019 the technical challenge was to make Fig rolls for which I already have a recipe on Only Crumbs Remain.
These Homemade Fig Rolls are from an old post, so I simply updated it. It has to be said the pictures left a bit to be desired. So I made some more just for the purpose of reshooting . They are also seriously yummy so okay, that might also have had something to do with it.
I could have left it at that but the signature challenge was to make a chocolate biscuit bar. Now I love making biscuits and cookies (I’ve written several books on them over the years) and I love chocolate (I’ve written a book of 100 chocolate recipes too) so how could I resist the challenge to come up with my own signature chocolate biscuit bar.
So here you have my Oat and Marshmallow Crispy Chocolate Bars and I hope you like them as much as my family did. It has to be said it wasn’t long before these were all eaten. A mixture of flavours and textures plus lots of chocolate they were too hard to resist.
The Oat Biscuit Layer
Hidden under the chocolate is a oat biscuit bake which is really easy to make. You simple melt the butter and sugar together and then stir in the flour and oats.
Next you press this into the base of a 20cm (8in) cake tin, pressing as level as you can with the back of a spoon or dampened finger tips.
Bake for 20 minutes then set aside while preparing the marshamallow and crispy rice layer.
Marshmallow and crispy rice
To make the chewy marshmallow with crispy rice layer, place the marshmallows in a heavy based pan with 2 tbsp milk. Heat gently over a very low heat stirring constantly until the marshmallows have completely melted.
Remove from the heat and stir in the puffed rice ( I used rice Krispies). Quickly spread in an even layer over the biscuit base.
The chocolate coating
To complete the chocolate biscuit bars they were cut into fingers and dipped in tempered milk chocolate. You can read all about how to temper chocolate here on my other recipe blog Recipes Made Easy.
I use a method called seeding as its really easy to master. First melt about 2/3 of the chocolate slowly. Remove from the heat before adding the remaining chocolate chopped into small pieces. Stir until completely melted.
The biscuits are then dipped in the now tempered chocolate. I find plain chocolate the easiest to temper but most of the family like milk chocolate best. So to get the best results and flavour I used 2/3 cooking milk chocolate (it tends to be easier to work with) and 1/3 my favourite eating (dessert) chocolate (for flavour).
To get a good finish when dipping in chocolate you will find it easier if you work with more chocolate than you actually need. I have given the quantity for the minimum amount required to get a decent finish. The more chocolate you have the easier it is.
Don’t worry any unused chocolate can be allowed to set and remelted to use for another recipe. But always use a chocolate that has not previously been melted for the seeding (eg the smaller amount).
To finish I drizzled a little melted plain chocolate back and fourth over the chocolate bars for decoration.
Oat and marshmallow Crispy Bites
I could not make up my mind if the bars I had made were too big, so I decided to make some smaller bite size biscuits although these are more like two generous bite sized.
If you want to make these you will need a little more chocolate for coating.
You can make 18 bars or 36 bite sized bars or as I did a mixture of the two.
Oat and Marshmallow Crispy Bars – Step by step
Oat and Marshmallow Crispy Bars
For the biscuit base
- 150 g (5oz) butter
- 150 g (5oz) golden caster sugar
- 150 g (5oz) rolled oats
- 150 g (5oz) plain flour (all purpose flour)
For the marshmallow layer
- 200 g (7oz) marshmallows
- 2 tbsp milk
- 75 g (3oz) puffed rice cereal
- 500 g (1lb 2oz) milk chocolate
- 50 g (2oz) plain dark chocolate (optional)
- 20cm (8in) shallow square baking tin
- baking parchment
To make the biscuit base
- Preheat the oven to 180℃ (160℃ fan)/350°F/gas mark 4. Line a shallow 20cm (8in) square cake tin with baking parchment.
- Place 150g (5oz) butter and 150g (5oz) golden caster sugar in a medium sized saucepan and heat gently over a low heat, stirring until the butter melts and combines with the sugar.
- Remove from the heat and stir in 150g (5oz) rolled oats and 150g (5oz) plain flour, beat until combined then tip into the lined tin and press into an even layer.
- Bake for 20 minutes. remove from the oven and set aside.
To make the marshmallow crispy layer
- Place 200g (7oz) marshmallows in a small heavy based pan with 2 tbsp of milk. Heat over a low heat stirring until the marshmallow has completely melted.
- Mix in 75g (3oz) puffed rice and stir to coat in the marshmallow. Tip on top of the biscuit base and spread level. Allow to cool completely.
- Line one or two baking sheets with nonstick baking parchment. Carefully remove the biscuit slab from the tin and cut into 16 bars or 32 bites or a mixture of the two with a sharp knife.
- Break 500g (1lb 2oz) milk chocolate into pieces and place about 2/3 in a bowl over a pan of gently simmering water (base of the bowl should not be touching the water). Heat gently stirring until the chocolate has melted.
- Chop the remaining chocolate into smaller pieces. Remove the bowl of melted chocolate from the heat and stir in the remaining chopped chocolate. Stir until melted.
- Carefully dip each biscuit bar into the melted chocolate to coat. Lift out of the bowl on a fork and allow the excess chocolate to drip back into the bowl. Wipe the base of the bar gently on the side of the bowl and transfer to the lined baking sheet, Repeat until all the bars have been dipped.
- If desired melt 50g (2oz) plain chocolate in a bowl over a pan of hot water and drizzle or pipe over the chocolate bars. Place in a cool place and allow to set.
- When melting chocolate water is the enemy. If any moisture gets into the melted chocolate it will “seize” and be unusable. To help avoid this make sure the water doesn’t boil as this will produce steam. the water should be only just simmering.
- When you remove the bowl from the pan wipe the base dry with a tea towel.
- Do not be tempted to lick your fingers when working with chocolate.
- For best results use more chocolate than you actually need – I used 600g (1lb 6oz) to make mine. If making bite sized bars you will need more chocolate.
- Pour unused chocolate onto clean baking parchment and allow to set. Wrap and use for other chocolate bakes.