Cross the Arno River on Ponte Vespucci and go straight to Borgo San Frediano (the third street). There you'll see a white cart with a few tables outside. Besides lampredotto panini (sandwiches) they serve pork, tripe, and sausage panini and even a few pasta and meat courses. This is traditional Florentine street food.
But we're heading to the other side of the wall, through Porta San Frediano (the gate) to Via Pisana, 2/r. Here you'll find Trattoria Sabatino, filled with locals.
Trattoria Sabatino has been around since 1956. They serve inexpensive lunches and dinners on weekdays (closed Saturday and Sunday). Three of us ate lunch for 42 euro (fall, 2008) that included a pasta course, meat course, and side dish along with a half liter of wine and mineral water.
There's a new menu daily that includes dishes they almost always have and a few seasonal dishes. Our first course dishes were a black cabbage and rice soup, tortelli stuffed with potato, and an unusual pasta, pasta sulle rigaglie di pollo, a sauce made with chicken giblets and cocks combs. Pastas and soups were priced at 3.50 to 3.70 euro. Portions aren't huge but two courses was plenty filling. Meats and fowl ranged from 4.50 euro to 5.10. There are a few basic antipasto dishes and several tempting desserts, too. Although nothing fancy, the food was excellent.
Save room for gelato, our next stop. Go back through the wall and walk along the river to the next bridge, Ponte Carraia.
More places to eat - Where to Eat Lunch in Florence