Lamb Poleko

Name: Lamb Poleko
Ingredients: 4 lbs leg of lamb, butter-flied; 2 cups ripe mangoes, chunks; 1 teaspoon black peppercorns; 1 teaspoon szechuan peppercorns; 1 cup chopped cilantro; melted butter, for basting; rub; 3 tablespoons curry powder; 1 teaspoon ground szechuan peppercorns (timur); 1 teaspoon turmeric; 1 teaspoon chili powder; 1 tablespoon garlic paste; 1 tablespoon ginger paste; 1 tablespoon tomato paste; 3 tablespoons honey; salt and pepper