Russets are high starch potatoes that work the best for fries, however yellow-fleshed potatoes like Yukon-Gold can be substituted. Do not use red-skinned potatoes. Their starch content is too low. They are more suited to potato salads and other dishes where you want the potatoes to hold their shape.
2 pounds potatoes, preferably russets, scrubbed
8 Tbsp vegetable oil, 1 Tbsp reserved
2 Tbsp cornstarch
1 tsp salt
1/2 tsp black pepper, ground
Adjust oven rack to middle position, place a pizza stone on the rack if you have one. Preheat oven to 450F.
Slice 1/8 inch lengthwise off both sides of each potato. Discard. Slice into 1/2 inch pieces lengthwise. Lay slices flat and slice into 1/2 thick sticks. Place potatoes in a microwave-proof bowl, cover tightly and microwave for 2 minutes. Toss potatoes gently, and microwave for an additional 2 minutes. Spread fries on a cooling rack and dry with paper towels.
Pour 7 Tbsp of vegetable oil on a large, rimmed baking sheet. Place baking sheet in oven for 5 minutes and allow the oil to begin to show wisp of smoke. In the bowl used to microwave potatoes, mix cornstarch, salt, pepper and 1 Tbsp oil. Add potatoes and toss.
Remove baking sheet from oven and arrange fries on the sheet in a single layer, using tongs to ensure even placement. Return to oven and cook for 15 minutes. Remove baking sheet and flip potatoes, using a metal fish spatula and tongs. Cook for an additional 15 minutes, checking after 10 minutes to ensure fries are not overly browned.
Remove fries from the oven and place onto a cooling rack with paper towels underneath. Allow to drain for 30 seconds and then serve immediately.