In a medieval synagogue on a 2nd-century street (which you can visit on a cellar tour), the Catalani family does exceptional modern plates (like an appetizer salad of raisins, walnuts, pomegranate, and marinated duck) as well as ancient Roman cuisine (like maiale alla mazio, a favorite pork dish of Julius Caesar’s), food as warm and comforting as the ambience. Finish with the delicately perfumed lavender panna cotta, a cream-based dessert.