How the waitress said "Only pie for dessert"? (6)
I believe the answer is:
tartly
'how the waitress said' is the definition.
I can't tell whether this definition defines the answer.
'only pie for dessert?' is the wordplay.
'only pie' becomes 'ly' (I can't justify this - if you can you should give a lot more credence to this answer).
'for' is a charade indicator (letters next to each other) (I've seen this in other clues).
'dessert?' becomes 'tart' (type of dessert).
'ly' after 'tart' is 'TARTLY'.
Can you help me to learn more?
(Another definition for tartly that I've seen is " In a caustic manner".)