Whisk water and salt together in bowl until salt dissolve. Pulse potatoes and salt water in food processor until coarsely ground, 10 to 12 pulses, stirring occasionally. Drain mixture in fine mesh strainer, pressing potatoes with rubber spatula until dry, discard liquid. Transfer potatoes to bowl and microwave, uncovered, until dry and sticky, 8 to 10 minutes, stirring halfway through cooking.

Stir flour and pepper into potatoes. Spread the potato mixture into thin layer over large sheet of aluminum foil and let cool for 10 minutes. Push potatoes to center of foil and place foil and potatoes in 8 inch square baking pan. Push foil into corners and sides of pan, smoothing it flush to pan. Freeze, uncovered, until firm, about 30 minutes.

Meanwhile, adjust oven rack to middle position and heat oven to 200°F. Set wire rack in rimmed baking sheet. Add oil to large pot and heat to 375°F. Using goil overhang, lift potatoes from pan anf cut inyo 48 pieces. Fry half of potato tots until golden brown and crisp, 5 to 7 minutes. Transfer to baking sheet and place in oven to keep warm.

For bacon-ranch tots; stir 1 tablespoon cider vinegar into potatoes after microwaving. Add 4 slices finely chopped bacon, 1 teaspoon onion powder, 1/2 teaspoon garlic powder with flour in step 2.