Even fourth-generation bakers make mistakes – especially when it comes to sourdough. But while your average bread-baking mishap might leave you with a dense and inedible loaf, one of Jason Geary’s errors became the basis of the recipe for his first Ciabattin loaf.

“We were working with a French chef who said it looked like a ciabatta in a tin,” says Geary, the CEO of Geary’s Bakeries and founder of Jason’s Sourdough, which he launched six years ago. Crucially, it was far more convenient than either sourdough or ciabatta had been in their traditional boule or baguette forms.