In a large bowl, whisk together buttermilk, salt, and 1 tablespoon chile pepper. Submerge catfish fillets in buttermilk mixture. Cover and refrigerate for at least 1 hour or overnight.
In the work bowl of a food processor, pulse potato chips until finely ground. In a large bowl, whisk together ground potato chips, cornmeal, flour, baking powder, and remaining ½ tablespoon chile pepper.
In a large Dutch oven, pour oil to a depth of 4 inches, and heat over medium-high heat until a deep-fry thermometer registers 365°.
Remove catfish from bowl, discarding buttermilk mixture. Dredge in potato chip mixture, ensuring both sides are fully covered. Working in batches, gently place catfish in hot oil. Fry until golden brown and cooked through, about 3 minutes. Let drain on paper towels. Serve immediately.
Recipe by Louisiana Cookin' at https://louisianacookin.com/spicy-cajun-fried-catfish/