The most common and most likely answer to this crossword clue is the 12 letter word INADEQUATELY
I've seen this crossword clue in The Guardian
I
N
A
D
E
Q
U
A
T
E
L
Y
Buddy explains!

The straight part
We know that "in shoddy fashion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in shoddy fashion = inadequately.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does INADEQUATELY mean?
INADEQUATELY adverb- In an inadequate manner.