Dense, stale bread is what you want. Sourdough, Italian bread (like a brioche), or French loaf are popular choices. I used u003ca href=u0022https://www.saraleebread.com/our-breads/artesano-breadu0022u003eSara Lee Artesano breadu003c/au003e for this recipe. It’s thick-sliced and slightly sweet which adds a nice flavor to the overall dish.