It's Bulgaria's classic hangover cure — each diner doses the bowl at the table with garlic vinegar and chili to taste, specifically to shock a rough morning back to life.
Beef or veal tripe is simmered for hours into a thick, milky, paprika-tinted broth, then finished tableside with vinegar, crushed garlic, and hot chili oil. Sofia's all-night eateries and market kitchens keep it on the menu around the clock.