In a stand mixer bowl, combine flour, salt, and oil. Gradually pour in water while mixing until a firm dough forms. Knead for 5-7 minutes.
Divide the dough into four portions, roll into balls, cover with cling film, and allow to rest for 30 minutes.
Filling
Option 1 (raw): In a bowl, combine the lamb, onion, chilli, parsley, coriander powder, cumin powder, salt and black pepper until fully combined.
Option 2 (cooked): Heat vegetable oil in a pan and fry the minced lamb until browned. Season with coriander, cumin, paprika, chilli, salt, and pepper. Remove from heat, cool slightly, then mix in onions and parsley.
Tomato Sauce
Parcook the split peas: cover with water, bring to a boil, then simmer until tender, about 20-25 minutes. Drain and set aside.
In a saucepan, heat oil over medium heat. Sauté onions until translucent. Add garlic and fry until fragrant.
Stir in tomato paste, vinegar, coriander, cumin, chilli pepper, and black pepper. Add the cooked split peas and 240 ml water. Simmer for 15 minutes until reduced.
Assembly
Roll each dough ball thinly on a floured surface. Slice into 2-inch squares.
Spoon meat mixture onto each square, fold by connecting opposite corners, seal the edges, and fold the sides.
Oil the steamer basket base. Arrange dumplings without touching each other. Steam for 15-20 minutes until cooked through.
Yoghurt Dressing
Mix yoghurt, labneh, lemon juice, zest, garlic, dill, and mint. Season to taste.
To Serve
Arrange steamed mantu on a serving platter. Pour tomato and split pea sauce over the mantu, drizzle yogurt sauce on top. Garnish with paprika and fresh herbs.
Notes
Filling, dough, and sauces can all be prepared a day ahead
Assembled mantu can be refrigerated covered with damp cloth before steaming