"Ga i baned? Os gwelwch chi'n dda."
Translation:May I have a cuppa ?Please.
Cwpan is a cup, the addition of 'aid' to the noun makes it 'cwpanaid' = 'a cup full'
This is the same for 'Llwyaid' = llwy + aid = 'a spoon full' and some other nouns to indicate a measure.
'Cwpanaid' has become 'cwpaned' over time and this is often abbreviated to 'paned'
Thus the full meaning of 'paned' is 'a cup full'
A common idiomatic use is with a beverage.
Thus 'paned o de' and 'paned o goffi'
This has been further contracted to just 'paned' on its own.