Whisk all sauce ingredients in a bowl until blended; set aside.
MAKE THE DUMPLINGS:
To make the filling, add all dumpling ingredients (except wonton wrappers) to a food processor and process until smooth. Transfer to a bowl.
Arrange the wonton wrappers on a dry work surface. Place 1 teaspoon of the filling in the center of each wrapper. Brush the edges of each wonton wrapper with water, then fold half circles (or triangles), pressing edges to seal. Repeat with the remaining filling and wrappers, to make 36 dumplings.
Place the prepared dumplings on a baking sheet that has been lightly dusted with cornstarch. Cover with damp paper towels to avoid drying them out.
Put 8 to 10 dumplings in a steamer basket; set in a saucepan over 1-inch of boiling water. Cover tightly and steam until the dumplings are cooked through, about 7 minutes. Transfer the dumplings to a serving tray. Serve immediately with the dipping sauce.
Look for wonton wrappers in the refrigerator case or produce section of your grocery store.
Oyster sauce will be found in the Asian section of your grocery store.
To toast sesame seeds, place them in a small dry skillet over medium-low heat. Cook, shaking the pan and stirring constantly, until fragrant, 1 to 2 minutes