They're split for soup (4)
I believe the answer is:
peas
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">they're split for soup</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for peas that I've seen before include "Legumes" , "Leguminous seeds" , "Podded vegetables" , "Vegetables from pods" , "Seeds in a pod" .)