Cut salted fish against the grain into thin slices. Rinse and soak for 5 minutes. Drain then pat dry with paper towels.
Heat 1 tablespoon vegetable oil in a wok or large fry pan. Combine eggs, ground pepper, and eggs in a bowl. Beat the eggs lightly with a fork. Pour into wok or fry pan. Allow eggs to set. Then stir fry for 1 to 2 minutes. Remove and set aside.
Add another 1 tablespoon vegetable oil to the wok or large fry pan. Stir fry prepared salted fish until golden brown, about 6 minutes. Remove and set aside.
Add remaining 3 tablespoons vegetable oil to the wok or large fry pan. Sauté garlic for 30 seconds. Then add beehoon, soy sauce, fish sauce, and ground pepper. Stir and toss noodles to get it well coated with the sauces. If it is a little dry, add 2 tablespoons of water.
Add kangkung (water spinach) and continue to stir fry for about 3 to 4. Then return eggs and salted fish to the wok or large fry pan. Toss to get eggs and salted fish well distributed. Turn off stove.
Dish into 4 individual plates. Serve immediately with Sambal Belacan.