I've been steeping two vanilla beans in some PG. I just gave it a try, and it seems to work.
The two vanilla beans have been steeping for about 2 weeks at room temperature in about 10ml of PG. I made up a quick 5ml batch of juice made with 4 parts MBV Bavarian Cream to 1 part of my vanilla bean extract. I mixed it stronger than I generally recommend for experimenting with flavors... 25%.
Mixed it well, loaded it with a new coil into a Kanger T2... and, wow, it works! Very vanilla-custardy! It can't handle too much heat, starts to taste just a little burnt... but at a moderate voltage it seems to work. I am little surprised, and definitely gratified.
I'll post an update after it steeps for a bit.
Did you cut up the beans prior to steeping?
Also, what colour is the final extract?
I sliced the beans in half lengthwise except the ends, so they stay in one piece.
The colour is a deep amber.
The beans I got came in a test tube, and that is what I used to steep them.
I had tried once before cutting the beans up, mixing them with PG in a glass bottle which I then put in a simmering pot of water for about 20 minutes. It was faster but just wasn't amazing. The cold steeping over 2 weeks is working better, the vanilla taste really comes through.