Taps with hard metal back one found in kitchen (4)
I believe the answer is:
chef
'one found in kitchen' is the definition.
(a chef works in a kitchen)
'taps with hard metal back' is the wordplay.
'taps' becomes 'ch' (cold and hot taps).
'with' says to put letters next to each other.
'hard metal' becomes 'Fe' (Fe is the atomic symbol for iron).
'back' is a reversal indicator.
'fe' reversed gives 'ef'.
'ch'+'ef'='CHEF'
(Other definitions for chef that I've seen before include "member of kitchen staff" , "French master" , "Kitchen head" , "Chief male cook in restaurant" , "Saucier" .)