I recently soaped the Pink Sugar from Wellington and it did the same thing. From everything I've read on the forum all of the Pink Sugar FOs are going to go dark brown no matter where you get them. Doesn't it smell great though?
I know, mine didn't even go dark evenly so not only is it a weird black brown color it's uneven. I'm hoping it will just keep getting darker until it all evens out. If anyone knows of a way to lighten it up at all, do tell.
Pink Sugar from just about every vendor that I know of off the top of my head goes dark brown because of the high vanillin content. Micas and/or even TD are completely useless with it. It'll still go brown over time.
Vanilla Stabilizer might help, but I've heard of a lot of hit-or-miss results. Hopefully someone who has had good results with it will chime in.
I use the Pink Sugar from ScentWorks and it smells fantastic, but it gives me dark brown soap that also lathers brown. I cut the amount of the FO down to .5 oz ppo once to see if that would help, and it did a little, but not by much- my soap went medium brown and lathered tan. The scent still held up pretty good at .5 oz ppo, for what it's worth.
I pretty much use it exclusively in my lotions, body butters, and perfume sprays now.
Soapsupplies.net has a Pink Sugar FO that discolors *less* than others. It still goes tan, and doesn't smell quite as nice as the SW version, but it works. I have several versions and even though it discolors almost black and gives a yellow/brown lather... I still prefer SW over all others.
FWIW, the Pink Sugar from WSP doesn't smell anything like the real one (and most other dupes), so don't be surprised if you order from somewhere else and it's totally different. It's not them, it's WSP that's off.
I soaped NG's with BC vanilla stabilizer about 6 months ago and it stayed pink. I just rebatched some trimmings I found in my soap cupboard. The scent held pretty well, too.
I shredded up one of my pink sugar bars and added to another batch with no FO. It turned out real nice. Just a faint scent of Pink Sugar and no discolor