How to make milk chocolate peanut butter cups

This was a bit of an experiment to see if I could manage something like Reese’s king size cups. I don’t really like these things but my sister does and they’re hard to find in the UK (and expensive). A fairly simple task I thought – chocolate, peanut butter, sugar. Reese’s list the ingredients as milk chocolate, peanuts, sugar, salt (& preservative) — via Instructables