Bring water to boil and add salt. Soak silken tofu in the salt water. This will prevent it from falling apart while handling and cooking.
Sauce: mix vegetarian oyster sauce, soy sauce, sweet potato starch, black bean paste, tomato ketchup, vegi Tom Yum Paste, sesame oil, minced ginger, sugar, and minced hot chili pepper together.
Cut silken tofu into serving sizes and lay them on a serving plate. Place the plate of tofu in the steamer. Wait until steam appears then place sauce over the tofu; this will prevent the sauce from dripping to the bottom. Cover and steam for 3 to 4 minutes. Serve.