Preheat oven to 400 F.
In a large bowl, combine the sweet potato, broccoli florets, 2 tablespoons vegetable oil, garlic powder, salt, oregano and pepper. Stir until the vegetables are well covered in oil and spices. Bake for 20 minutes.
Meanwhile, combine the brown rice and water in a pot. Bring to a boil and simmer for 25-30 minutes or until all the water is absorbed.
Coat the tempeh with barbecue sauce and place on a baking sheet. Roast for 10 minutes.
In a small bowl, whisk together the vegetable oil, apple cider vinegar, honey, mustard and salt and pepper.
When everything is cooked, combine the rice, sweet potato, broccoli and tempeh. Top with cabbage slices, scallion, pumpkin seeds and dressing.