Preparation Set a strainer in a 13x9x2" glass baking dish. Combine half of all ingredients with 5 tablespoons water in a processor and purée until smooth. Strain mango mixture into dish. Purée the remaining ingredients with 5 tablespoons water and strain mango mixture into dish. Freeze until mixture is slushy, about 2 hours. Working in 2 batches, purée in processor again. Return mango ice to same dish. Freeze 2 hours. Repeat 2 more times. DO AHEAD: Can be made 2 days ahead. Cover and keep frozen. Let stand at room temperature for 30 minutes. Scoop into dishes, sprinkle with chile powder, if desired, and serve.
Preparation Set a strainer in a 13x9x2" glass baking dish. Combine half of all ingredients with 5 tablespoons water in a processor and purée until smooth. Strain mango mixture into dish. Purée the remaining ingredients with 5 tablespoons water and strain mango mixture into dish. Freeze until mixture is slushy, about 2 hours. Working in 2 batches, purée in processor again. Return mango ice to same dish. Freeze 2 hours. Repeat 2 more times. DO AHEAD: Can be made 2 days ahead. Cover and keep frozen. Let stand at room temperature for 30 minutes. Scoop into dishes, sprinkle with chile powder, if desired, and serve.