If you’re making the gravy, make it first. Heat a skillet over medium heat. Add the oil and flour. Whisk to combine, and cook the raw flavor out for a couple of minutes. Whisk in the turmeric and paprika. Cook for a minute or so. Whisk in the minced garlic and shallot. Cook for 1 minute, then whisk in the chicken stock, oyster sauce, light soy sauce, dark soy sauce, sesame oil, and white pepper.

Make your cornstarch slurry by combining the cornstarch and water (stir well before adding, as the cornstarch settles quickly). Drizzle it into the gravy mixture, whisking constantly. The gravy should be on the thicker side so it won’t immediately seep into the bread of the sandwich. Remove from the heat and cover until you’re ready to serve the sandwiches.

In a wok or deep pot, add your frying oil (it should be at a depth of a few inches). Heat the oil to 350°F/175°C. The oil temp will lower when you drop the egg mixture in, and the optimal frying temperature is 325°F/160°F. Use a thermometer to check and maintain the temperature. When your oil is close to the target temperature (NOT BEFORE), make your batter.

To a large mixing bowl, add the cooked protein, diced onion, and mung bean sprouts. Add the sesame oil and cornstarch, and crack the eggs into the bowl just before you’re ready to fry. Use a large soup ladle to fold the mixture together until just combined. The eggs should look slightly beaten and only just mixed with the rest of the ingredients. Do not overmix.

By now, your oil should be at the right temperature. Fill your ladle with about ¾ cup of the mixture, and tilt the ladle close to the oil, starting from the edge where the oil meets the wok. Slowly pour the batter in, with the ladle barely touching the oil. Prolonged contact between the ladle and the oil will cause the egg to cook while it’s in the ladle and stick, and you won’t have a smooth drop for the next patty. Once the patty has released from the ladle, you can push it away from the edge. Repeat to drop in two to three scoops of the mixture. Take a break to quickly clean and dry the ladle if needed.

Fry the patties for 40 seconds. Gently ladle some hot oil on top of each patty to help them set more quickly. When each patty is solid and turning golden brown on the bottom, flip (in the same order you dropped them in). Fry for 1 more minute.

Scoop each patty onto a mesh strainer (first in, first out), giving it a few taps and a gentle squeeze to remove excess oil. Place each patty on a wire rack (or paper towel) on a sheet pan to drain. Repeat to cook all 6 patties. If you’re not serving with the gravy, lightly sprinkle salt over the fried patties.

To build a sandwich, spread a good amount of mayonnaise on each slice of bread. Add a leaf of lettuce to each piece, and top one of the bread slices with an egg foo young patty. Spread a spoonful of gravy over the top. Then add the sliced tomato, pickles, and a sprinkle of chopped scallion. Cover with the other piece of bread, cut in half, and serve with gravy on the side.

You can dip the sandwich into a little ramekin of gravy or pour it over each bite to your heart’s content!