Wash hands with soap and water.
Scrub garlic and ginger with a clean vegetable brush under running water. Pat dry with a clean towel. Then, slice the garlic and mince the ginger.
Gently rub broccoli, mushrooms, red bell pepper, and green onions under cold running water. Pat dry with a clean towel. Cut the bell pepper and green onions.
Set a large wok or skillet over medium-high heat. Once heated, add the oil.
When the oil is hot, add the garlic and ginger, and stir fry for one minute. Then add the broccoli, mushrooms, and bell pepper. Stir fry for 2 minutes, stirring constantly.
Add the rice wine vinegar, brown sugar, soy sauce, and water. Cover and cook until the broccoli is tender, about 4 to 5 minutes.
Add the tofu and cook 2 minutes more.
Garnish with the sliced scallions and serve over brown rice.