Shuck the corn and remove all the silk, then stand each cob upright and carefully cut the kernels away from the cob by angling your knife slightly inward until you have about four cups.

Heat the larger portion of oil in a wok or pot over medium-high heat, then add the onions and lower the heat to medium. Stir often until the onions turn a deep golden brown and begin to char at the edges, which should take about 8 to 10 minutes.

Use a slotted spoon to transfer the charred onions to a plate, leaving any remaining oil in the wok. Add the final teaspoon of oil and return the heat to medium-high.

Add the corn to the hot oil and cook while stirring occasionally until the kernels begin to pop and take on a bit of char. If the kernels start popping too vigorously, use a lid to partially cover the pan.

Cook until the corn is tender but still has a snap, roughly 2 minutes, then season with salt and chile flakes and fold the reserved onions back in to serve.