Bread-Bakers v109.n012.1

One vital key to the result you want is not the recipe...but rather 
the oven. To get that great crust you want, one needs an oven that 
provides a lot of initial steam and then vents the moisture out at 
the last few minutes.

The bakeries supplying the restaurants use wonderful deck ovens that 
have steaming and venting mechanisms built in.

Home ovens (especially most gas ovens) have a harder time creating 
and holding steam in. Most bread baking books describe a variety of 
methods to do so with a home oven.

Finally, the standard rule of thumb is that in order to get the chewy 
open crumb you desire you need to use a very wet dough (70% hydration 
or more). And use less kneading/mixing and more folds to preserve the 
irregular internal structure.

Hope this helps.

Allen
SHB
San Francisco