Place the bean curd in a blender and process until smooth. Set aside. Finely chop the scallops, prawns and celery. Place in a bowl. Add the corn kernels, reserved tofu, salt, pepper, chicken powder, 1 teaspoon of cornstarch, sugar and sesame oil and mix well. To form the mixture into a lute shape, dip Chinese spoons into vegetable oil. Fill the spoon with the tofu mixture. Repeat until all the mixture has been used. Place spoons in a bamboo steamer over high heat and steam until mixture is firm, 5 to 7 minutes. Remove from steamer and carefully remove mixture from spoon. Heat some vegetable oil in a non-stick saucepan over medium heat. Lightly dust the “lutes” with cornstarch, add to the pan and cook until lightly browned on one side, then flip and cook until second side is lightly browned. Meanwhile, reduce chicken stock over medium high heat. Season with salt, pepper, 1 teaspoon of sugar and 1/2 teaspoon of sesame oil. After a few minutes, add 1 tablespoon cornstarch to 1 tablespoon water and stir into chicken stock. Simmer until thickened, about 2 to 3 minutes. To serve, place the tofu on a plate and dress lightly with the sauce.