I stopped by on Saturday (3/23/2013) at 9:00am and found out that Nerbone serves breakfast. You can have their sandwiches or a plate of meat with bread on the side. The choices for both are boiled beef or boiled stomach, with choice of spicy or pesto sauces. It indeed was one of the best sandwiches I've ever had. The meat was extremely juicy and tender. The spicy sauce (red) was hot, but not Korean food hot. It definitely accentuated the sandwich without masking the taste of the meat.
And there was no line in the morning. The tables were also relatively empty. They speak some English, and a little patience is needed when ordering if you don't speak Italian, but excellent service overall.
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