It was also my first experiment with aquafaba (the water from chickpeas); it really seems to be the new generation of egg substitute! Loved it. It's said that, generally, adding 3 TBS of aquafaba should substiutute 1 egg (but it's not a rule).
As for the glaze I used her suggestion, except that it went "wrong"... or right, it's a matter of perspective :P I couldn't AT ALL beat the glaze with a handmixer; chocolate flew everywhere, LOL! I just put some gloves on and worked on the ingredients until they formed a big gooey dough and looked like cake fondant.
From The Vegan 8