This is my Unk. Bonita Verte fig. The plant is in a 2 gal pot and has about 10 figlets, out of those 2 are doubles!
This is the only plant that shows this anomaly.

I believe that happens when the fig suffers some kind of damage when forming but don't bet any money on my answer. If I'm wrong I'm sure someone will correct me :)

I cannot tell you if there was any damage, I think not, esp. a few figs at the same time. Nothing has changed over the last few months really, even the watering schedule is the same.

It could have been an insect or even getting bumped. 

My hardy Chicago threw several figs like that and a few other odd shapes last year.  They tasted just as good.  :)

My new LSU Gold has a "double fig" like that on it.

I used to have that problem. I just moved my plants away from the nuclear reactor and they stopped doing that ;)

Figs have some very strange deformities when they're young...but as they mature, the malformations usually go away. It's just a phase that fig trees go through. I've seen fruits like that on my trees too.

Thanks for sharing! Best of luck this season!

Just pray it's a far relative of Dall'Osso ;)