Preheat oven to 375 F. Drain tofu and slice in half lengthwise, then in half crosswise, to create 4 rectangular pieces. Place in a small baking dish. Mix together soy sauce, garlic, ginger, sriracha sauce, and sesame seeds, and drizzle over tofu. Place baking dish on top rack of oven and cook for about 15 minutes, until golden brown. While tofu is baking, place baguette slices on a small baking sheet and place in oven to toast for about 5 minutes, until browned and crisp. To arrange sandwiches, place one toast on a serving dish, layer with one-fourth of the lettuce leaves, 1 slice of baked tofu, and 1 slice tomato. Repeat to make 4 open-face sandwiches. Serve immediately.
Note: To make a breakfast sandwich in minutes, bake the tofu the day before and refrigerate until the next morning. Then simply pop the baguette slices in the toaster and add the tofu (warm or cold), tomatoes, and lettuce.
Nutritional information per serving: 173 calories, 11 g protein, 6 g fat, 0 g saturated fat, 13 g carbohydrate, 2 g fiber, 2 g sugar, 283 mg sodium.