Peel and slice the potato thinly. Soak in water, drain, and place in a microwave-safe container. Sprinkle 1 tbsp water, cover loosely with plastic wrap, and microwave at 600W for 2 minutes. Pat dry.

Cut open the mentaiko and extract the inner contents.

Mix the mentaiko, mayonnaise, and pepper in a bowl to create the mentai mayo sauce.

Brush half of the olive oil onto a spring roll wrapper. Arrange half of the potato slices on one half of the wrapper, spread 1/4 of the mentai mayo sauce over the potatoes, and fold the wrapper. Repeat to make 2 pieces. Spread the remaining mentai mayo sauce evenly on top and layer them. Sprinkle pizza cheese on top.

Place the layered pieces on a baking tray lined with aluminum foil. Bake in a toaster oven for about 6 minutes until golden brown.