In a pan, melt together the chocolate, butter and golden syrup until smooth.
Take off the heat. Pour the Digestive nibbles into the pan and stir through.
Add the marshmallows and give a quick stir.
Pour the chocolate mixture into the lined pan and spread it around evenly, smoothing the top.
Pop the tray into the fridge and chill until set. This should take around two hours or you can also leave it overnight.
Cut into slices and serve!
Notes
Recipe tips
Make sure you melt the chocolate, butter and golden syrup together. If you add a cold ingredient into warm chocolate it will seize. Seized chocolate goes grainy and bitty and is no longer smooth and shiny.
If your chocolate does seize, you can bring it back by adding a small amount of milk (1-2 tablespoons to start). Stir really well and it should become smooth and glossy again. If not add another tablespoon and stir again. Be careful not to add too much milk as this could make the mixture too runny.
If you prefer you can melt the ingredients together in a microwave instead of in a pan. Put the chocolate, butter and golden syrup in a microwave-safe bowl, heat for 30 seconds on high/full power, then stir well. Heat again for 30 seconds then stir again. If needed, repeat again and stir until smooth.
Try not to put the marshmallows into the hot chocolate mixture if it is really hot, as they might melt. If your chocolate seems really hot allow it to cool slightly first.
To make neat slices in your rocky road, put your knife in a jug of hot water and let it warm up before using it. Dry the knife with a tea towel before cutting. Put the knife back in to warm up again and then repeat, making sure you dry it before using it each time.