Heat the oil in frying pan over medium high heat.
Add mustard seeds, and curry leaves. Add the red pepper as the seeds crack. (As you add the curry leaves it will splatter; be careful.) Add cabbage, carrots, bell pepper, and beans. Stir-fry three to four minutes, until the vegetables are crisp but not overcooked.
Turn off the heat, add salt, lemon juice and coconut, mix well.
Serve warm or at room temperature.