Put a large nonstick pan on the highest temp it can take. Add a large splash of veg oil. Once hot, add the broccoli and fry about 2 minutes until it's softened but still crisp, with some scorched bits. Remove the broccoli to a plate.

Repeat the above step with the carrot, then red pepper, then mushrooms.

Add another splash of veg oil to the pan and sear the beef. Once no pink remains, add the onion, garlic, and ginger and fry 1 minute. Sprinkle in the cornstarch and give everything a stir.

Combine the hoisin and rice vinegar, along with several grinds of freshly cracked black pepper. Pour it into the pan. Add 1/2 cup cold water and stir until the sauce thickens. Return all the veg to the pan and toss. Serve with freshly steamed rice.