Peel the potatoes and cut them into evenly sized 1 to 2-inch chunks.

Place the potato chunks in a medium pot and cover with cold water. Add 1 teaspoon salt to the water if desired.

Bring to a boil over medium-high heat, then lower the heat and simmer for 15 to 20 minutes, or until fork-tender.

Drain the potatoes well.

Measure about 850g boiled potatoes, or around 4 cups mashed potatoes, and transfer them to a large mixing bowl.

Mash the potatoes until smooth and free of lumps.

While still warm, add glutinous rice flour, cornstarch, shredded cheese, salt, and pepper.

Mix and knead until a smooth dough forms.

Line a rectangular pan or dish with plastic wrap. Transfer the dough into the pan and press evenly into a uniform layer.

Cover and freeze for 30 minutes to firm the dough.

Remove the dough from the freezer, turn it onto a cutting board, and peel away the plastic wrap.

Cut into 8 sticks, about 1 x 1 x 6 inches each. For a crispier finish, lightly press lines onto the surface with the back of a knife.

Heat oil to 320°F (160°C).

Fry the Potato Cheese Sticks for 5 minutes until lightly golden. Remove and let them rest on a cooling rack.

Increase the oil temperature to 350°F (175°C).

Fry again for 30 seconds to 1 minute, until golden brown and crispy.

Remove and drain on a rack or paper-lined plate.

Sprinkle with salt and chili pepper powder, or serve with ketchup while hot.