Kangaroo eating large crusty loaf (7)
I believe the answer is:
bloomer
'crusty loaf' is the definition.
(I've seen this before)
'kangaroo eating large' is the wordplay.
I cannot quite understand how this works, but
'large' could be 'l' (eg in clothes sizes) and 'l' is found within the answer.
The remaining letters 'boomer' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for bloomer that I've seen before include "A slangy blunder or flower in blossom" , "Mistake (colloq.), loaf" , "that's made with flour!" , "Large slip" , "Large loaf; or, a mistake" .)