Step 1

Bring 10 cups water to a boil in a large stockpot over high; reduce heat to medium-low, and maintain a simmer.

Step 2

Meanwhile, use a mandoline fitted with a waffle blade or use a wave waffle cutter to cut potatoes into waffle-shaped slices. Drop potato slices, in batches, into simmering water, and cook, stirring occasionally and adjusting heat if necessary to maintain a simmer, until translucent, about 3 minutes. Using a spider or slotted spoon, gently remove potato slices from water, and arrange in a single layer on a wire rack set inside a rimmed baking sheet. Let stand until cool, about 25 minutes.

Step 3

While potatoes cool, heat canola oil in a large, deep Dutch oven over medium-high to 400°F. Working in batches, fry potato slices until outside of potato is firm, about 30 seconds. Transfer potatoes to a wire rack set inside a baking sheet to drain. Transfer drained potatoes to a parchment paper–lined baking sheet to cool, and freeze until frozen, 30 to 45 minutes. Reduce heat to low, keeping oil warm until ready to use again.

Step 4

Stir together berbere and salt in a small bowl. Set aside.

Step 5

Reheat oil to 400°F over medium. Working in batches, fry potatoes, stirring often, until golden brown, about 2 minutes. (Adjust heat between batches to maintain temperature as needed.)

Step 6

Using a spider or slotted spoon, remove fries from oil, and drain on a wire rack over a baking sheet. Sprinkle spice mixture over hot fries.