SWIM uses a
Magic Bullet, with the coffee grinder blade.
But before, its important to pre-break it to smaller amounts, unless you want to break it and also risk pieces flying to your direction. SWIM first frays it with the hand, making each mimosa piece into a couple of thinner layers (sometimes gotta fold the mimosa pieces a few times for you to be able to separate the layers).
Then, gotta cut the thinner pieces into smaller squares/rectangles, maybe a couple of centimeters in size (or more or less the size of computer keyboard keys). If you just put the thin and long pieces inside the blender, the fibers will wrap around the blade and lock it, so it can break it.
It is quite a lot of work all in all, and your fingers get blackish (and sometimes it doesnt come off for a couple of days even with strong scrubbing or alcohol), and also sometimes you get a bit cut or rough skin. But its nice work somehow, like working in nature.
A lazy friend of SWIM has another technique.. He always does an A/B extraction.. So he pre-breaks just a little with the hand, and then puts it in acidified water, and leaves it for many days. The acidity softens up the bark after a while... So after a few days, he uses the blender to break it down a bit. Then some foam forms, so he just lets it settle for another few days.. Then he uses the blender again, and let it stay for a few more days. His process takes a couple of weeks even, but he has no rush. In the end it seems to work, but SWIM preffers the method above of pre-breaking with the hand, fraying and then coffee grinder.