Herb of mint family (5)
I believe the answer is:
thyme
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">herb of mint family</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for thyme that I've seen before include "Aromatic ingredient" , "Aromatic shrub" , "Ingredient in cooking" , "Culinary adjunct" , "A herb; sounds like prison sentence" .)