Prepare the bread: Trim the crusts from each slice of white bread. Then, cut each slice diagonally into two triangles, creating a total of 24 triangles.

Make the shrimp mixture: In a medium bowl, combine the finely chopped shrimp, chopped green onions, minced garlic, grated ginger, egg white, soy sauce, sesame oil, and white pepper. Mix thoroughly until all ingredients are well incorporated.

Add cornstarch: Sprinkle the cornstarch over the shrimp mixture. Mix again until the cornstarch is fully incorporated. This will help bind the mixture and give it a slightly chewy texture.

Spread the shrimp mixture onto the bread: Generously spread about 1 to 2 tablespoons (15-30g) of the shrimp mixture onto one side of each bread triangle. Ensure an even layer, pressing gently to adhere it to the bread.

Heat the oil for frying: Pour the vegetable oil into a large skillet or wok, ensuring there is enough depth for shallow frying (about 2.5cm or 1 inch deep). Heat the oil over medium-high heat until it reaches 180°C (350°F). You can test the oil temperature by dropping a tiny piece of bread; it should sizzle immediately and turn golden brown within a few seconds.

Fry the shrimp toast: Carefully place a few shrimp toast triangles, shrimp-side down, into the hot oil. Do not overcrowd the skillet, as this can lower the oil temperature and cause the toast to stick together. Fry for about 2-3 minutes per side, until the bread is golden brown and crispy, and the shrimp mixture is cooked through and opaque.

Drain the shrimp toast: Once golden brown and cooked, remove the shrimp toast from the oil using a slotted spoon or spider strainer. Place them on a wire rack set over a baking sheet or on a plate lined with paper towels to drain any excess oil.

Serve: Arrange the crispy shrimp toast on a serving platter. Serve immediately while warm and crisp. Optionally, serve with a side of mayonnaise mixed with chili garlic sauce for dipping.