Handle good egg in which found second of yolks, most surprising! (10)
I believe the answer is:
broomstick
'handle' is the definition.
(I know that broomstick is a type of handle)
'good egg in which found second of yolks most surprising' is the wordplay.
'good egg' becomes 'brick' (both can mean a dependable person).
'in which' means one lot of letters goes inside another.
'found second of yolks' becomes 'o' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'surprising' indicates an anagram.
'most' is an anagram of 'omst'.
'o'+'omst'='oomst'
'brick' enclosing 'oomst' is 'BROOMSTICK'.
Can you help me to learn more?
(Other definitions for broomstick that I've seen before include "Potter's equipment" , "for traveller at Halloween?" , "hag-ridden" , "Handle" , "it has a dreadful woman driver" .)