Does old yeast still work?!
It is 2 1/2 years old and I am curious if would still work okay.
Answers:
no if you have kept it in the fridge or in a cool place perhaps ,but I would just get new one rather then wasting a bunch of flour and other ingredients over 1 little packet of old yeast.
It probably won't work, but you can 'proof' it first by dissolving it in a little warm water. If the water becomes bubbly, the yeast is OK.
If the yeast is beyond its expiration date, chances are that it will not work. It's pretty touchy stuff.