In a large skillet, preferably cast iron. heat the coconut or other neutral oil over medium-high heat.
When the oil starts to shimmer, add the cumin and mustard seed. Stir then cover with a lid. The mustard seeds will pop in a matter of minutes. When the ruckus dies down, reduce heat to medium, add the chile and turmeric and tip in the chopped green beans.
Stir so the green beans get a nice coating of the spiced oil, then add the coconut flakes and curry leaves, if you have them.
Mix together and cook for another few minutes, until the coconut smells and looks toasty, and the green beans are still bright green but yield to the tooth..
Turn off heat, add sea salt and, I suggest, a squeeze of lime juice. Pluck out the curry leaves and enjoy warm, room temperature or chilled.