Yeast. Sometimes it lets you down.

I am a baker of bread. It's enjoyable to me to add the yeast to warm liquid and a little sugar and watch it bubble and grow. For the most part, it's quite dependable. Tonight's project was making a few holiday babkas, which for me, is now a very pleasant task. I measured out the milk, and heated it to a precise 105-115 degrees. (A ten degree leeway is far precise enough for me.) After adding a few teaspoons of sugar to feed the yeast, the bowl was placed in a warmish place so it could bubble and froth, signaling me that I could continue on with my recipe. 10 minutes later, the yeast had still not stepped up to the plate, leaving me (and my starter) deflated and disappointed. My mise en place was assembled and I was ready to move forward. In my excitement to create some tasty babka, I had forgotten a crucial thing- yeast can be a big let down. And theres no warning- good yeast looks just like bad yeast, and it's not going to let you know ahead of time that it's not bringing it's best game. So, long story short, always make sure you have back-up yeast. Or just lower your expectations.