It's way out having gold cake (6)
I believe the answer is:
gateau
'cake' is the definition.
(gateau is a kind of cake)
'it's way out having gold' is the wordplay.
'it's way out' becomes 'gate' (I've seen this in another clue).
'having' says to put letters next to each other.
'gold' becomes 'Au' (Au is the chemical symbol for gold).
'gate'+'au'='GATEAU'
(Other definitions for gateau that I've seen before include "Something French for 22?" , "Richly decorated cake" , "Cream dessert cake" , "Fancy cake" , "Calorie-laden cake" .)