Vegan Recipe Substitution

I'm making a vegan version of kourabiedes -- little crumbly Greek butter cookies. The recipe I'm working from calls for an egg yolk -- I guess for savory fat reasons, but I'm not certain. Any suggestions for a vegan egg yolk?

It's probably there as an emulsifier, so something like soy lecithin.

hm. ok. can i buy that at a supermarket? what would it be sold as?

i am c+p'ing a googled answer since i've only read about using finely ground flax seed+water

"For every one egg I use: 1 Tbsp ground flax seed + 3 Tbsp of hot water. Mix it up and let it cool a minute or two... as it cools it will take on an "eggy" consistency!"

from here: http://tribes.tribe.net/thesecretlifeofaveganbaker/thread/4c93f540-47dd-4d2a-8ece-60d3f9dd4a65

i did this ^^ and it worked pretty well. thanking u.

fwiw, it's sold as lecithin - not sure about everyday groceries, but natural food stores always have it. It's a brown thick liquid. Good to know the flax worked.