Process herbs and dressing ingredients in a food processor until finely minced; season with salt and pepper.
Grill sliced eggplant until charred and tender, then set aside.
Grill tomato halves until charred and softened, then set aside.
Toast flatbread or pita until crispy, then cut into pieces and coat with olive oil.
Toss chickpeas with dressing, then assemble on a platter with grilled vegetables and sliced spring onion. Drizzle with remaining dressing and garnish with herbs and croutons.
Notes
Use fresh herbs for the best flavor and adjust seasoning to taste.