Curried Tuna Tartare on Pappadam

Name: Curried Tuna Tartare on Pappadam
Ingredients: 1 1/2 tablespoons water; 1 1/2 teaspoons mayonnaise; 2 teaspoons sour cream; Salt and pepper to taste; 12-ounce tuna steak; 1/2 cup cucumber, peeled, seeded, cut into 1/8-inch dice; 2 tablespoons finely chopped chives; Juice of 1/2 small lemon; 8 shots of hot sauce, or to taste; 1 1/2 cups vegetable oil; 1 package plain pappadams, 11/4-inches in diameter; 1 teaspoon vegetable oil; 2 teaspoons finely diced onion; 1 teaspoon curry powder; 2 teaspoons finely diced apple; 1/2 banana, finely diced