For peanut sauce: Combine the peanut butter, soy sauce, rice vinegar, ginger and 2/3 cup hot water in a small bowl. Mix until smooth. Set aside.
Heat about 1 tablespoon oil in a large saute pan over medium high heat. Add the chicken and frozen mixed veggies. Cook until the chicken is warmed thru and the veggies are hot, about 5 to 7 minutes, stirring frequently.
Cook the noodles according to package directions.
Pour the peanut sauce over the cooked chicken and veggies. Lower the heat to medium low and cook, simmering, for about 4 to 5 minutes or until hot and the sauce is thickened.
You can either pour the sauce over the cooked noodles in a bowl or on a platter, or dish the noodles up individually and pour the chicken/veggie mixture over the top. Sprinkle with some chopped salted peanuts, if you wish!