Heat 2 teaspoons of oil in a pan or wok. Add sliced tofu and stir-fry until all sides are brown. Do this in batches if needed. Transfer to a plate and set aside.
Add remaining oil. Stir-fry garlic and onions until fragrant and translucent. Add carrots and stir-fry for 2 minutes. Add green beans and water. Continue cooking until vegetables are crisp-tender.
Stir in bean sprouts, fried tofu, oyster sauce, fish sauce and dried shrimp. Keep stir-frying for another 2 to 3 minutes until cooked through. Season with salt and pepper. Serve warm. Enjoy on its own or as a side dish.
