A lovely thing about this dish is that it can be a meal for vegetarians or carnivores alike, and nothing says summer like eating with our fingers. Eating outside means we have permission to pick up all sorts of things — from chicken wings and hot dogs to these lamb–and vegetable–filled rollups. This is the way it works: Set out a pile of lettuce leaves, a pile of fresh herbs, some ground chile, a bowl of store-bought chickpea dip (hummus), and some instant chive-yogurt sauce. Heap the grilled vegetables on one platter, the cooked lamb on another.