Prepare salad by combining all vegetables, herbs, avocado and peanuts in a large bowl. Set aside.
Make dressing by combining soy, sriracha, sugar, ginger, garlic and rice wine vinegar. Slowly whisk in sesame oil to emulsify. Set aside.
Preheat your grill over medium heat. Season flank steak with salt and pepper. Spray grill with Pam and grill for 6-7 minutes per side.
Remove from grill, tent with foil and let rest for 10 minutes.
Meanwhile, cook spaghetti according to directions. Drain then rinse with cold water until noodles have chilled, or do this earlier and place noodles in the refrigerator.
Slice flank steak into thin strips. Add to salad.
Add dressing and toss to mix. Serve on chilled plates.