Using a knife or a mandoline, slice the potatoes 1/8 inch thick. Place the sliced potatoes in a large bowl, filled with water and 2 tablespoons of the salt. Allow the potatoes to soak for at least 30 minutes.
Drain the potatoes, place them on paper towels, and pat dry.
In a small bowl, stir together the pepper and remaining 1 tablespoon salt. Set aside.
In a 5-quart stock pot or a Dutch oven, combine the canola and olive oils with the garlic. Heat the oils to 300 to 325°F over medium heat. Carefully drop potato slices into the oil in small batches and cook, stirring occasionally, 12 to 15 minutes. Using a slotted spoon, carefully remove the chips once they are a deep golden color, and place on a plate lined with paper towels to drain the excess oil.
Immediately sprinkle the chips with the salt and pepper. Repeat until all the potatoes are fried. Allow the chips to cool for 10 minutes before serving.