Slice the king oyster mushrooms into thick pieces, about 2cm wide.

Make shallow cuts on both sides of the mushroom slices, about 1/4 of the thickness. Avoid cutting too deep to maintain their shape.

Heat a frying pan over high heat and add an adequate amount of cooking oil.

Place the mushroom slices in the pan and cook, flipping occasionally, until both sides are golden brown.

Reduce the heat to low, add the butter, and let it melt while coating the mushrooms evenly.