Start by preparing all of the vegetables. Cooking will go quickly, so having everything prepped will make things easier.

Add the soy sauce, water, rice wine vinegar, sesame oil, sugar, cornstarch, red pepper flakes and mustard powder to a bowl, and stir to combine well. Set it aside.

Add about one inch of water to a deep non-stick skillet, and bring it to a boil. Add the broccoli and cook for about three minutes or until it’s just shy of how tender you like it. Drain it, and run cold water over the broccoli so it stops cooking. Set it aside to finish draining.

If there is any liquid left in the skillet, dry it, and then add the vegetable oil, heating it over medium-high heat.

Add the mushrooms and red peppers, stirring regularly, and letting them cook for about five minutes or until the peppers are softened.

Add in the light-colored parts of the onion, the ginger and garlic, and saute for another minute or so, until you can really smell the ginger and garlic.

Dump in the broccoli and stir to combine the ingredients. Once the broccoli is heated back through, pour in the sauce you prepared earlier, and continue stirring constantly, being sure to coat the vegetables in the sauce.

Once the sauce thickens to your liking and the vegetables are hot, remove the skillet from the heat and serve immediately, topped with the dark green onions.

I served mine with lo mein noodles. You could also eat this with rice or just by itself.