Wash and scrub the russet potatoes well; leave the skins on for texture. Using a mandoline with a waffle/Crinkle-cut blade or a V-slicer with a rotating motion, cut the potatoes into 3–4 mm (about 1/8–3/16 inch) thick waffle cuts: slice once, rotate the potato 90 degrees, then slice again so the blade cuts the lattice pattern. Keep the pieces uniform in thickness for even cooking.

Rinse and soak

Place the cut waffle fries in a large bowl of cold water and swish to remove surface starch. Drain and refill with fresh cold water. Soak for 30 minutes (or up to 2 hours in the refrigerator) to remove additional starch and help achieve crispiness.

Dry thoroughly

Drain the potatoes and spread them on clean kitchen towels or paper towels. Pat completely dry — any surface moisture will cause oil splatter and reduce crispness.

Heat oil

Pour oil into a heavy-bottomed pot or deep fryer to a depth of about 3–4 inches (enough to submerge fries). Heat oil to 325°F (160°C) for the first blanch. Use a thermometer to monitor temperature.

First fry (blanch)

Working in small batches (do not overcrowd), fry the waffle fries at 325°F (160°C) for 3–4 minutes until they are softened but not browned. Remove with a slotted spoon or spider and drain on a wire rack set over a baking sheet. Let cool 5–10 minutes. Return the oil to 375°F (190°C) for the final fry.

Second fry (crisp)

When oil reaches 375°F (190°C), fry the blanched waffle fries in small batches for 2–3 minutes or until golden brown and crisp. Remove and drain on a wire rack or paper towels.

Season

Immediately sprinkle coarse kosher salt and freshly ground black pepper over the hot fries so seasoning adheres. If using the optional seasoning mix, combine smoked paprika, garlic powder, onion powder, and cayenne in a small bowl, then sprinkle over the fries to taste and toss gently to coat.

Serve

Serve the waffle fries hot with desired dipping sauces. For best texture, serve within 10–15 minutes of frying.

Dipping Sauce (optional)

Combine mayonnaise, ketchup, yellow mustard, hot sauce, lemon juice, and salt in a small bowl. Whisk until smooth. Taste and adjust seasoning (add more hot sauce for heat, more lemon for brightness). Chill for 15–30 minutes to let flavors meld before serving.