Foreigner mum has to provide eggs for! (5)

'foreigner' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'mum has to provide eggs for' is the wordplay.
I cannot quite understand how this works, but
'mum' could be 'ma' (ma can mean mother) and 'ma' is found within the answer.
The remaining letters 'lay' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...

Can you help me to learn more?