Cooking range covered in eggs and herb (7)
I believe the answer is:
oregano
'herb' is the definition.
(oregano is a kind of herb)
'cooking range covered in eggs' is the wordplay.
'cooking' indicates an anagram.
'covered in' indicates putting letters inside.
'eggs' becomes 'oo' (visually resembles two eggs).
'range' is an anagram of 'regan'.
'regan' inserted within 'oo' is 'OREGANO'.
'and' is the link.
(Other definitions for oregano that I've seen before include "Herb related to marjoram" , "food flavouring" , "Sweet-smelling herb" , "leaves for season" , "Wild marjoram" .)