Sandwich source
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sandwich source</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for deli that I've seen before include "Unusual food shop" , "Food shop (abbr)" , "Food shop (colloq.)" , "Food shop or counter" , "Fine-food store" .)