Grew up with the stuff... And made some here, too - had to bring in the rum from Germany, though, as they don't sell the 54% rum here. (Lidl did once, several years ago - but only once.)
You don't need a recipe, really. Use half to same amount of sugar as fruit, brown or white (I prefer it less sweet) - make sure fruit is sound, clean and dry when you add it - use 54% rum if you can (better keeping quality - you could also add some pure alcohol to make up the percentage, but then that's difficult to get in Britain, too...).