1. 1. Prepare Your Baking Dish and Oven: Preheat your oven to 375 F (190 C). Lightly grease a 9×13 inch baking dish or a similar oven-safe pan. This prevents sticking and makes cleanup easier.

2. 2. Saute Aromatics: In a medium skillet or saucepan, heat the olive oil over medium heat. Add the chopped onion and cook for 3-5 minutes until softened and translucent. Stir in the minced garlic and grated ginger (if using) and cook for another minute until fragrant. Be careful not to burn the garlic.

3. 3. Whisk Together the Flavorful Sauce: In a medium bowl, combine the chicken or vegetable broth, soy sauce, rice vinegar, brown sugar, chili oil, sesame oil, and red pepper flakes (if using). Whisk well until the brown sugar is fully dissolved and all ingredients are thoroughly combined. Taste and adjust the chili oil to your desired spice level.

4. 4. Arrange the Dumplings: Place the frozen potstickers or dumplings in a single layer in your prepared baking dish. Try to space them out evenly to ensure they cook through properly and get a nice crisp texture on the edges.

5. 5. Pour and Bake: Carefully pour the prepared sauce mixture evenly over the dumplings in the baking dish. Make sure each dumpling is coated in the sauce. Transfer the dish to the preheated oven and bake for 20-25 minutes, or until the dumplings are cooked through, tender, and the sauce has thickened slightly and is bubbling. The edges of the dumplings might get slightly crispy, which is a desirable texture.

6. 6. Garnish and Serve: Once baked, remove the dish from the oven. Garnish generously with fresh chopped cilantro and a sprinkle of sesame seeds. You can also drizzle a little extra chili oil over the top for an added kick, if desired. Serve hot and enjoy!