Was able to stomach eel tart (with 6A 24 27) - doubtful at first! (9)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

( Anagram of [with MUCH ADO ] EEL TART containing [ ABOUT ] O [character representing NOTHING ]) + D ( initial letter of [at first] D OUBTFUL) – once again using MUCH ADO ABOUT NOTHING (6a/24/27) as the anagram and containment indicators