Boiled oatmeal (8)
I believe the answer is:
porridge
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">boiled oatmeal</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for porridge that I've seen before include "type of bird" , "Breakfast dish - spell in prison" , "Morning oats" , "Possibly breakfast - time in prison" , "milk and oats together" .)