Cut the bamboo shoot in half lengthwise. Slice the tip into 1cm wide pieces and the base into 1.5cm wide pieces. Cut the king oyster mushrooms into halves lengthwise, then slice into 2–4 pieces for bite-sized portions.

Spread out aluminum foil and place the bamboo shoots and mushrooms on it. Sprinkle with salt and pepper, drizzle with soy sauce, and top with pieces of butter.

Fold the aluminum foil tightly, sealing the edges well. Cook in a toaster oven for about 10 minutes until the mushrooms are cooked through.