Add water to the bowl of the rice cooker, and place the bowl in the chamber of the rice cooker.
Apply a light coat of sesame oil to the surface of the steaming basket to prevent the dumplings from sticking when you're ready to serve them.
Arrange the dumplings in a single layer in the steaming basket and place the basket in the bowl of the rice cooker.
Place the lid on the rice cooker and turn it on. Let the dumplings steam for 10 to 20 minutes. Frozen dumplings take a bit longer to heat through completely.
Carefully open the rice cooker and let the steamed dumplings rest for 5 minutes to allow the excess moisture on the surface of the dumplings to evaporate.
Remove the steaming basket from the rice cooker and transfer the steamed dumplings to a serving tray.
Serve the steamed dumplings with equal parts sesame oil and soy sauce for dipping.