The most common and most likely answer to this crossword clue is the 17 letter word IVORIEST/ESTONIAN
I
V
O
R
I
E
S
T
/
E
S
T
O
N
I
A
N
Buddy explains!
The straight part
We know that "creamier than the rest" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case creamier than the rest = ivoriest/estonian.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.