To make wontons ahead: Freeze the unbaked wontons on a parchment-lined baking sheet. (Do not refrigerate the wontons; the moisture from the vegetables will seep into the wonton wrappers and turn them into mush.) When you are ready to bake, brush or spray a thin layer of oil over the frozen wontons; do not thaw. Bake the frozen wontons at 400ºF for about 12 to 13 minutes.
For the wontons:
- 4 1/2 tablespoons vegetable oil, divided
- 2 cloves garlic, minced
- 1 tablespoon minced ginger (from a 1-inch piece of ginger)
- 5 cups thinly sliced Napa cabbage (green cabbage is also ok)
- 1 large carrot, grated (about 1 1/3 cups grated)
- 3/4 cup frozen peas, thawed
- 2 scallions, thinly sliced
- 3/4 teaspoon salt
- 1/2 teaspoon toasted sesame oil
- 1 large egg
- 48 to 50 square wonton wrappers
- 4 1/2 to 5 ounces cream cheese
For the dipping sauce (optional):
- 3 tablespoons soy sauce
- 4 tablespoons rice vinegar
- 3/4 teaspoon toasted sesame oil
1 Prepare the filling: Heat 1 1/2 tablespoons of the vegetable oil in a wok or large skillet over medium-high heat. When the pan is hot, add the garlic and ginger and cook until fragrant, 30 to 60 seconds.
Add the cabbage and cook, stirring frequently to prevent burning, until it starts to wilt, about 2 to 3 minutes. Add the grated carrot, peas, scallions, salt and sesame oil and cook for another minute.
Turn off the heat and dish the vegetables onto a plate to cool for 10 minutes.
2 Preheat oven to 400ºF. Position an oven rack in the center position. Brush 2 large baking sheets with oil (1 tablespoon per pan), spray with cooking spray, or line with parchment. (Wontons baked on parchment won't get quite as crispy on the bottoms.)
Lightly beat an egg for the egg wash and set aside.
3 Fold the wontons: Lay 4 wonton wrappers on a work surface. Place about a tablespoon of vegetable filling in the center of each wrapper. Place about 1/2 teaspoon of cream cheese on top of the vegetables.
Using your fingers, brush the egg wash along the edges of the wonton wrappers. Lift 2 opposite corners of the wrapper and pinch them together at the top. Lift the other two corners towards the top and pinch them against the first two corners to form a pyramid. Pinch edges of the wrapper together to seal the wonton closed.
Repeat with the other three wontons. Transfer the sealed wontons onto one of the sheet pans and cover loosely with plastic wrap to keep them from drying out.
Repeat filling and folding the wontons until you have filled a baking sheet with 24 to 25 sealed wontons. Remove the plastic wrap and brush a thin layer of oil on all of the wontons or spray with cooking spray.
4 Bake for 11 to 12 minutes, or until the edges of the wontons are a deep golden brown color.
5 While the first batch of wontons is baking, prepare a second batch of wontons using the remaining filling. Once the first batch is done baking, bake the second batch.
6 To serve: Let the wontons cool for a few minutes before serving. Whisk together the ingredients for the dipping sauce and serve with the warm wontons. These baked wontons are best consumed in the same day.