In a bowl mix the ground beef, breadcrumbs, cilantro, mint, milk, and season with salt and pepper. Dampen hands with water and roll the mixture into equal sized balls.
Preheat a nonstick pan on medium heat. Place the meatballs in the pan and brown on both sides. Once nicely browned remove from the pan and set aside.
Heat the oil in a pot over medium low heat. Add the onions and minced garlic and cook for 2 - 3 minutes until the onions are fragrant and softened.
Add curry powder, turmeric, garam masala, coconut milk, crushed tomatoes, and broth. Bring to a simmer for about 5 minutes. Add the meatballs to the pan and simmer for another 8 minutes. Taste and season with salt and pepper accordingly.
Drizzle the pita with remaining olive oil, lemon zest, season with salt and pepper. Warm under the oven broiler on low for 2 - 3 minutes and cut into quarters. Serve and garnish with extra mint and cilantro.