Sweet sauce (7)
I believe the answer is:
custard
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sweet sauce</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 custard that I've seen before include "Sweet sauce made with milk and eggs" , "Cooked mixture of milk and eggs" , "Type of apple" , "Egg/milk bake" , "Pudding sauce" .)