Even in a city obsessed with stunt dishes, the kumpir is an awe-inspiring thing. The KFC Double Down has got nothing on this Turkish twice-baked potato. The insides are scooped out and puréed with sheep’s-milk cheese and butter, packed back into the jacket, then topped with various ingredients. At Istanbul Café, you can top your kumpir with red cabbage, pickles, sliced olives, corn, Russian salad, and/or hot-dog-like sliced beef sausage. On top of it all go squirts of ketchup and mayonnaise, which slide together into a pink sludge. It’s a total monstrosity and completely scrumptious.