Young child eating a second slice at breakfast? (5)
I believe the answer is:
toast
'breakfast?' is the definition.
(toast is often eaten as breakfast)
'young child eating a second slice' is the wordplay.
'young child' becomes 'tot' (tot can mean a baby or toddler).
'eating' indicates putting letters inside.
'second' becomes 's' (common abbreviation).
'slice' indicates putting letters inside (some letters slice into others).
'tot' going around 'a' is 'toat'.
'toat' placed around 's' is 'TOAST'.
'at' is the link.
(Other definitions for toast that I've seen before include "Drink to someone" , "Warm, it may be eaten" , "Drink one's health" , "making this pledge?" , "Raising of glasses" .)