Combine first 4 ingredients in a large saucepan; bring to a boil. Reduce heat, and simmer 5 minutes. Add juice, pepper, shrimp, and tofu to pan; bring to a boil. Cook 2 minutes or until shrimp are almost done. Combine cornstarch and water in a small bowl, stirring until smooth. Add cornstarch mixture to pan; cook 1 minute, stirring constantly with a whisk. Slowly drizzle egg white into pan, stirring constantly. Remove from heat; stir in chili oil and onions.