Cook the Noodles: Boil the rice noodles according to the package instructions. Drain and rinse under cold water to prevent sticking.
Prepare the Veggies: While the noodles are cooking, prepare the vegetables by slicing the cabbage, carrots, and cucumber. Chop the cilantro and green onions.
Make the Peanut Sauce: In a bowl, whisk together peanut butter, soy sauce, rice vinegar, lime juice, maple syrup, sesame oil, and Sriracha (if using). Add water a little at a time to reach the desired consistency.
Assemble the Salad: In a large mixing bowl, combine the cooked noodles, cabbage, carrots, and cucumber. Pour the peanut sauce over the top and toss to combine evenly.
Garnish: Top with fresh cilantro, green onions, chopped peanuts, and sesame seeds if desired.
Serve: Enjoy immediately or refrigerate and serve chilled.
