Cut the potato into 1cm wedges and soak in water for 5 minutes. Drain and microwave in a heatproof container covered with plastic wrap for 5 minutes at 600W. Let cool.

Place the potato and potato starch into a resealable bag. Seal and shake until the potato is evenly coated.

Heat vegetable oil in a frying pan over medium heat. Add the coated potato wedges and cook for about 5 minutes until golden and crispy. Season with salt and pepper.

Prepare the Mentaiko Cheese Sauce: Remove the mentaiko roe from its casing. Microwave cream cheese and milk in a heatproof container covered with plastic wrap for 1 minute at 600W. Mix until smooth, then add the mentaiko and stir.