Line a 9" square tin with parchment paper and leave to the side. Prep your ingredients.
In a large bowl, add your chopped digestives, hazelnuts and mini marshmallows, and the first 16 Ferrero Rocher.
In a different large glass bowl over a pan of simmering water, add your milk chocolate. Make sure the water doesn't touch the bottom of the bowl, and stir occasionally.
Once melted, add the Nutella and butter to the chocolate and mix together until combined.
Once mixed, pour over the dry ingredients and mix everything together carefully.
Pour it all into the tin, and make sure its even. Press onto the top another 16 Ferrero Rocher pieces if you want one per piece. Let it set in the fridge for 5-6 hours or more.
Once set, cut into pieces (I do 16), and enjoy!
Notes
I used milk chocolate for this, but you can easily use dark chocolate as well.
I decided to use Ferrero Rocher in the rocky road, as well as decorating on top. This is because when Ferrero Rocher are on offer, I like to buy a lot.. but I realise its expensive, so its optional.
This recipe will last for 1+ weeks, in the fridge. And outside the fridge on a cold day.