
Prep the shrimp: Finely chop the shrimp, then toss with 1/8 tsp salt, 1/4 tsp sugar, and 1/2 tsp cornstarch. Set aside while you prepare the gravy.
Start the gravy: Heat 2 tbsp neutral oil in a medium saucepan over medium heat. Whisk in the flour, turmeric, and paprika, and cook for 15 to 20 seconds to form a light roux.
Build the flavor base: Add the minced garlic and finely minced shallot or red onion. Cook, whisking, for about 30 seconds until fragrant.
Make the gravy: Slowly whisk in 3 cups of the chicken stock until smooth. Bring to a gentle simmer, then stir in the oyster sauce, light soy sauce, dark soy sauce, sesame oil, and white pepper.
Thicken the gravy: In a small bowl, mix 3 tbsp cornstarch with the remaining 1/4 cup chicken stock. Stir about two-thirds of the slurry into the simmering gravy and cook for 30 seconds, until thick enough to coat the back of a spoon. Add more slurry if needed. Cover and keep warm.
Heat the oil for frying: Pour about 6 cups neutral oil into a wok or deep, heavy pot and heat to 335 to 350°F (170 to 175°C). Use a thermometer for accuracy, since the patties can burn or fall apart if the oil is too hot or too cool.
Mix the egg foo young batter: In a large bowl, combine the shrimp mixture, diced onion, bean sprouts, eggs, scallion, sesame oil, and the remaining 1 tsp cornstarch. Gently fold just until combined. Do not overmix, or the batter can become watery.
Fry the patties: Carefully ladle about 3/4 cup of batter per patty into the hot oil, frying 2 to 3 patties at a time without crowding the pan.
Cook until golden: Fry each patty for about 2 minutes on the first side. Spoon a little hot oil over the tops to help them set, then flip and fry for 1 to 2 minutes more, until golden brown and cooked through.
Drain and repeat: Transfer the cooked patties to a wire rack or paper towel-lined tray to drain. Continue frying until all the batter is used. This recipe makes about 6 patties.
Serve: Arrange the shrimp egg foo young patties on plates, spoon some warm gravy over the top, and serve immediately with steamed rice and extra gravy on the side.