• Cut your scallions, garlic and ginger up to a day before you plan to make the filling.
• Stir the soy sauce, mirin, oyster sauce, sesame oil and sambal olek together up to a day before you plan to make the filling.
• Cook, cool and store your filling for up to one day ahead of time.
• Make the wontons a couple hours, up to a couple months ahead of time. Store in the freezer.