*Note from Slow Cooker Central* - Due to the added 1/2 cup liquid I would suggest increasing the chocolate to 800g as per feedback comments below for better setting*
Instructions
Break up chocolate and put in the slow cooker, add the butter, condensed milk and baileys. Leave lid off during cooking.
Stir every 10 - 15 minutes for around 1 and a half hrs on low (times vary with each slow cooker).
Pour into prepared 20x20cm baking dish lined with baking paper and allow to set.