tl;dr

Slices of the cranberry-walnut bread served at Parc, in Philadelphia, and Le Diplomate, in Washington, D.C. Each bite delivers the sensation of eating an entire meal.

I loved this article, would recommend y'all read it instead of skimming to the end to find the bread

The best free restaurant bread I've had was at a Brazilian steakhouse, which for those unaware is all-you-can-eat steak.

I believe this was due to their financial incentive of having me load up on bread.