Cut the sirloin steak into thin strips and season with salt and pepper.
In a large Zip Lock bag or container, add the steak, green peppers, onion, broccoli, carrots, and garlic.
Next pour the entire bottle of sauce over steak and vegetables.
Fill the bottle with water and add that too.
Add in soy sauce, sriracha sauce, and red pepper flakes.
Seal the bag and shake so that all of the ingredients can marinate in the liquid.
Refrigerate and Marinate until ready to grill.
Heat up the Blackstone griddle to a low-medium heat with cooking oil.
Slowly and carefully pour the entire bag onto the griddle.
Cook and toss until steak is cooked and vegetables are soft and fragrant.
Add in the cooked brown rice noodles and toss again. Quickly pull off once tossed to prevent sticking.
Serve hot and enjoy!