Yeast is alive, and it’s been my muse for decades. Here’s an excerpt from my journal, dated 10/27/2008, when Ruth was four years old.

R was on her stool in the kitchen when I transferred the fresh yogurt into a clean glass jar. "How do you make the yogurt?" she asked.

"Yogurt is milk with a culture in it," I told her. "It’s a bacteria, a little tiny animal. I warm up the milk so it’s all cozy for the bacteria and then it grows."

"Like the bread!" she said instantly.

"That’s right!" Yeast is a little tiny animal, just like the bacteria in the yogurt. It needs to be warm and cozy to grow. 

When I was in college I’d teach people to bake bread, kneading it by hand in my apartment by Union Square. "The bread is alive," I would say. "When you knead it you want it to feel like your earlobe, alive and springing back." 

When R was a baby, I would change her diaper and squeeze her chubby thigh. It would remind me of a strand of challah dough, warm and soft and alive. Now she’s a little girl with a warm cookie in her hand. She understands as deeply as I do that food is alive, literally living and breathing.  

And I have to say that I was wrong back in 2008, because yeast is NOT a little animal, it’s a fungus, botanically, but it IS alive, a single-celled organism. As it grows, it releases gas; that is the alchemy that makes the holes in the bread. Back when Ruth was little, I was baking with commercial yeast, the kind that comes in tiny dried granules. It is a cousin to the wild yeast that leavens the sourdough I bake now. To make bread rise, any yeast needs to be 1) warm and 2) wet and 3) fed by the starches and sugars in the other ingredients in the dough.

When I am baking bread, I am manipulating time and temperature. They work together to nurture the yeast. When the yeast is warm, close to body temperature, it grows faster. When it’s cooler, it grows more slowly. I manipulate the temperature a lot in order to make a bake schedule that fits into my day. If I’m going to have a long meeting in the morning, I keep the dough in the fridge so the rise is just as long as the meeting. I’m constantly moving glass jars around the house, to all the places I know are warmer or cooler: the window sill (cool in the evening), the back porch (warm in the afternoon), the fridge (obviously, cool), the dresser in the bedroom. I’m trying to control how fast the yeast grows, so that it’s ready when I am ready.

The timing I used for this bread experiment is complicated. I made a schedule for the four stages of bread making. For each of the six weekly batches, I set eight timers for the precise intervals in the process. The “mix” stage, for example, has five steps and takes three timers. For the dough to be ready at all of those time markers, I kept it warmer or colder, so it grew the right amount for each step. 

This is why sourdough baking got so popular during shelter-in-place: it takes a lot of time while you are in your house. You have to get through all of these steps, and you have to take the time between the steps while a living, breathing thing grows organically. You can’t do it on a weeknight after the kids go to bed. I didn’t try to master sourdough until my children were teenagers. Working with sourdough is, in a very small way, like tending to a child. There’s a rhythm to bathtime, storytime, bedtime snuggles. You have to be in tune with your small child to craft an evening routine that will settle them to sleep, warm and cozy in their bed. It is a little, just a little, like crafting a routine for bread dough: window sill, coil fold, back porch, banneton, final proof. Then bake and eat.