On any given night you can find crowds gathered on the sidewalk outside this cramped, noisy, hole-in-the-wall North Ender, jostling for the chance to dive into some of the freshest homestyle Italian cooking in Boston. Pomodoro is not fancy; it’s cash only, and offers only two wine choices, house red and white. But it is damn good. Our advice: While you wait for a table, nibble from a plate of crisp, lightly fried calamari with tomato sauce, and save room for pastas, seafood, and veal dishes that sing with simple bold flavors. Ever-present properietor Siobhan Carew makes this place a gem.