Combine all the ingredients in a saucepan over medium-high heat. Bring to a boil, cover, and reduce heat to low. Simmer for 15 to 30 minutes or until the plums are completely cooked.
Pour into a food processor or blender and mix until smooth.
Taste and add the remaining 1 tablespoon honey and rice wine vinegar. Let the sauce come to room temperature before storing in an airtight container in the fridge.
Combine all the ingredients in a food processor or blender and blend until smooth. If you make the sauce ahead of time, it will solidify in the fridge. Leave it out at room temperature for about 30 minutes before using.
Preheat the oven to 400 degrees Fahrenheit and line a baking sheet with parchment paper.
Defrost the package of spring roll shells at room temperature for 30 minutes.
Take the skin off the duck breasts. Cut the breasts into smaller pieces and add to a food processor. Cut one of the breast skins in half and add it to the food processor. Pulse until well combined. Add Chinese five-spice powder, salt, and black pepper and pulse again until combined.
Heat a skillet over medium heat. Add the ground duck and cook until browned, about 2 to 3 minutes.
Transfer to a plate with a paper towel to absorb the excess juices. Add the duck to a bowl and mix in the cilantro and Peanut Sauce.
Set up your spring roll wrapping station. Open the package of spring rolls, take them out, and keep a damp cloth or paper towel over them as you wrap.
Take a spring roll wrap and place it on a flat surface with one of the corners facing you (so it looks like a diamond). Brush with a thin layer of vegetable oil.
On the lower third of the wrapper, spread a thin layer of the Plum Sauce. Place a tablespoon of duck meat on top of the sauce and then drizzle a little bit of the Peanut Sauce on top.
Pull the bottom corner up and over, covering the filling. Roll it over once and then fold the two sides into the center. Tightly roll it up.
Place the spring rolls seam side down on the lined baking sheet. Bake for 9 minutes on one side, flip, and then bake for another 9 to 10 minutes. Serve with the Peanut and Plum Sauces on the side.