Cut tops off small peppers or halve large peppers lengthwise. Remove membranes and seeds. In a 4-quart Dutch oven immerse peppers in boiling water for 3 minutes. Remove; drain peppers, cut sides down, on paper towels.
For filling, break noodles. In a saucepan cook noodles and seasoning according to package directions. Add shrimp, and cook 30 seconds more. Drain noodle mixture, discard liquid. Return noodle mixture to pot. Add tofu, if using, hoisin sauce, bok choy, pea pods, green onions, and crushed red pepper; heat through.
Arrange peppers, cut sides up, on a serving platter. Spoon filling into peppers. Spoon any remaining filling around peppers. Sprinkle with toasted sesame seeds. Serve warm, or refrigerate and serve cold. Makes 4 servings.