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 spinach, pine nuts, pomegranate, and gorgonzola) as well as ancient Roman cuisine (like maiale alla mazio, a favorite pork dish of Julius Caesar’s). The food is as warm and comforting as the ambience. Finish with the delicately perfumed lavender panna cotta, a cream-based dessert.