Combine soy sauce, pineapple juice, ginger, 1 clove garlic, brown sugar, and cornstarch in a small bowl and set aside.
In a medium saucepan, bring 2 cups water to a boil. Add 1 cup brown rice and reduce heat to minimum. Simmer, covered, for 45 minutes.
Meanwhile, cut up veggies. Sauté onions and garlic (I use at least two cloves) in olive or grapeseed oil until soft. Add veggies in the order they appear (carrots, broccoli, pepper, mushrooms, pineapple). Remove from wok, set aside, and fry tofu to your desired crispness.
Push tofu to the side of the wok, whisk up the sauce, and add it in. Stir until thick and bubbly. Add all the veggies back in, stir until heated through, and serve over brown rice.