Rejuvinating expired yeast
I have half of a two-pound bag of Red Star Dry Active Yeast that expired in 11/19, and it's no longer proofing as it once did. (Sadly, I had the unctioning to buy another bag in January but didn't. Big mistake.)
Is there any way I can rejuvenate the yeast I have so that it proofs again? Or am I out of luck?