In a large bowl, whisk together the flour and 1 teaspoon of salt. Pour in the hot water and stir with chopsticks until crumbly. Add the cold water and knead until a smooth dough forms. Cover and rest for 30 minutes.

Heat 1 tablespoon of vegetable oil in a skillet over medium heat. Add the beaten eggs, scramble until just cooked, then remove from heat. Chop into small pieces and let cool completely.

In a mixing bowl, combine the ground beef, soy sauce, sesame oil, oyster sauce, white pepper, minced ginger, and remaining 1 teaspoon of salt. Stir vigorously in one direction until the mixture becomes slightly sticky.

Toss the chopped chives with a small drizzle of oil to prevent them from releasing excess moisture. Fold the chives and cooled scrambled eggs into the beef mixture until evenly distributed.

Divide the rested dough into 12 equal portions. Roll each piece into a 6-inch circle. Place about 3 tablespoons of the beef filling onto one half of each circle.

Fold the dough over the filling to create a half-moon shape. Press the edges firmly to seal, then crimp or pleat the edges tightly to ensure they do not open during cooking.

Heat the remaining 3 tablespoons of vegetable oil in a large skillet over medium heat. Place the turnovers in the pan and cook for 3 to 4 minutes per side until golden brown and crispy.

Add a splash of water (about 2 tablespoons) to the skillet and immediately cover with a lid. Let steam for 2 minutes to ensure the beef is fully cooked. Remove the lid, let the remaining moisture evaporate, and serve hot.