1. Heat nonstick skillet over medium-high heat, and add half of tofu cubes. Cook 10 to 12 minutes, or until cubes are golden, stirring occasionally. Transfer tofu to plate, and repeat with remaining tofu.
2. Stir together soy sauce, sriracha, vinegar, maple syrup, sesame oil, and 2 Tbs. water in small bowl. Return all tofu to pan, and add soy sauce mixture. Bring to a simmer, and cook 2 to 3 minutes, or until most of liquid is absorbed. Remove from heat, and stir in green onions and mayonnaise. Serve warm or chilled.