When we wrote *Ideas in Food: Great Recipes and Why They Work*, we had no vision of having a doughnut shop. Fast forward 10 years, and it seemed only appropriate to revisit the Sourdough Doughnut recipe to integrate into the lineup at Curiosity Doughnuts. Like the original recipe, our retooled formulation relies on a commercial yeast assist to leaven the doughnuts. Hopefully, as this new starter gains strength and life, we will be able to dial back the additional yeast. For now, the doughnut is light with a sourdough chew. It is our most robust doughnut. It will be fun to explore its place among our daily doughs.