In a large nonstick saute pan, heat the oil over medium heat. Add the bell peppers and mushrooms and cook, stirring occasionally, until just tender and slightly brown, about 5 minutes. Add the pork, stirring until no longer pink, about 5 more minutes. Add the rice, broth, soy sauce and salt. Bring to a simmer, cover, reduce heat to low and cook until the rice is tender, about 20 minutes.
Meanwhile, combine the garlic, ginger, lime juice, fish sauce, sugar and cayenne in a small bowl and stir until the sugar is dissolved. Set aside.
Remove the pork dish from the heat, add the garlic-ginger mixture and stir well. Serve in individual bowls and top with chopped scallions and radishes.