Ha ha, I am with Deborah!! How can I answer that?
Also because "favourite" can be interpreted so many ways...best workhorse item, thing that makes you feel most special when you put it on, thing you can't imagine doing without in the closet (i.e. core essential), thing that you or others associate most with you (signature).
I honestly love almost everything in my closet! And what I don't love, I really like!
However...here are a couple that were surprises, in a way, which makes them extra fun.
Both my two piece dresses (summer and winter) -- I did not expect to like them as much or find them as versatile, but I reach for both in their respective seasons again and again.
Leopard print silk shirt -- such a beautiful piece to wear. Always feel 500% in it.
J. Crew utility coat -- oh how I wish they would make this style again. It is SUCH a great coat for me in so many ways I cannot even count. And no, the shorter version will not do it for me. Needs to be this length. Please, J. Crew. Do it again!!
Comrags dress -- best summer dress ever!
Reiss tuxedo jacket.
Pure Amici cashmere "hoodie" -- oh my gosh I am glad I sprung for this during NAS. It was pricey for me but it has lasted. Yes, it pills a bit -- but it's amazing how often and how easily I wear it, with everything from jeans to fancy dresses.
LL Bean Mariner -- because WORKHORSE!!