Fill a bowl with cold water. You’ll be soaking the slivered potatoes in the water later. This prevents the potatoes from oxidizing after they’re cut and it washes away some of the excess starch.
Cut the potato in half, crosswise. Lay the potato halves flat side down on your chopping board. Slice each half into thin planks, slightly less than 1/8-inch thick. Stack a few of the planks and slice into thin slivers. Continue until you have finished slicing all the potatoes. Transfer the slivered potatoes to the bowl with cold water.
Peel the carrot and cut them into 3-inch sections. Slice each section into matchstick pieces.
When you are ready to cook the potatoes, drain them from the water.
Heat the canola oil in a wok over medium to medium-high heat. Add the garlic, ginger, Sichuan peppercorns, and red pepper flakes, if using. Cook for 30 seconds, until fragrant.
Next, add the potato slivers and cook for about 2 minutes, stirring occasionally. Add the carrots, bell pepper, white pepper, and salt. Stir to combine. Cook for another 2 to 3 minutes. The outside of the potato should be slightly soft but the inside still crisp.
Transfer the potatoes to a plate. Finish the dish with a light drizzle of chili oil, if you like.