Arrange the dumplings on a parchment- or silicone mat-lined sheet pan (don’t overcrowd it) and cook until hot, about 12 minutes. Serve immediately.
If you're finding the tops of the dumpling wrappers to be dry, cover the dumplings with an oven-safe baking dish or bowl to act as a lid. You can also steam the dumplings in a covered bamboo steamer basket.