Heat a cast iron or other heavy skillet to medium-high heat. Add the oil. When the oil is shimmering, but not smoking, add the corn kernels. Allow corn to cook without stirring for 2-3 minutes. This lets the kernels get a little char. After 2-3 minutes, stir kernels then let cook undisturbed again for 2-3 minutes. Continue this for 8-10 minutes total – stirring every 2-3 minutes – until the kernels are bright yellow with slight charring.