Stir 2 tablespoons water and cornstarch together in a bowl.
Place pork in shallow bowl and add cornstarch mixture and 1 teaspoon salt; stir to coat and let sit for a few minutes.
Mix 3 tablespoons water, sugar, soy sauce, MSG, and 1 teaspoon salt together in a bowl until sauce is smooth.
Heat oil in a wok or large skillet over medium-high heat; saute pork until pork is cooked through, about 5 minutes. Push pork to a side; add sweet bean paste. Cook and stir bean paste until fragrant, about 1 minute. Pour in the sauce and stir until thickened, 2 to 3 minutes.
Transfer pork mixture to a dish and top with spring onions.