Finely grind all garam masala spices in a spice grinder.
Wash the rice, soak it in water for 30 minutes, then drain.
Peel and finely grate the ginger.
Heat oil in a heavy-based pan over medium-high heat.
Add mustard seeds and wait for them to start popping.
Add the chilli, potato, carrot, and green beans to the pan.
Stir in turmeric and 1 teaspoon of garam masala for one minute.
Add the ginger and sauté for another minute.
Add the drained rice to the pan and reduce heat to medium-low.
Gently stir the rice for two minutes to coat it in oil and spices.
Add 570ml water and salt, then bring to a boil.
Cover with a tight lid, reduce heat to very low, and cook for 25 minutes.