Lemon-Pepper Catfish Nuggets With Peperoncini Dip

Ingredients

• 1 cup sour cream
• ¼ cup buttermilk
• 2 Tbsp. finely chopped peperoncini, plus 2 Tbsp. brine
• 1 Tbsp. finely chopped chives
• ¼ tsp. Diamond Crystal or Morton kosher salt
• ¼ tsp. freshly ground pepper
• 2 lb. catfish fillets, preferably US–farmed, cut into 1½" pieces
• 1 tsp. paprika
• 4 tsp. Diamond Crystal or 2½ tsp. Morton kosher salt, divided
• 1 cup buttermilk
• 1 cup rice flour
• ½ cup yellow cornmeal
• 8 Tbsp. lemon-pepper seasoning (no salt added), divided
• Vegetable oil (for frying; about 8 cups)
• Celery sticks (for serving)
• A deep-fry thermometer

Steps

1. Whisk 1 cup sour cream, ¼ cup buttermilk, and 2 Tbsp. peperoncini brine in a small bowl until smooth. Stir in 2 Tbsp. finely chopped peperoncini, 1 Tbsp. finely chopped chives, ¼ tsp. Diamond Crystal or Morton kosher salt, and ¼ tsp. freshly ground pepper. Cover dip and chill until ready to use. Do Ahead: Dip can be made 1 day ahead. Keep chilled.
2. Rinse 2 lb. catfish fillets, preferably US–farmed, cut into 1½" pieces; pat dry. Sprinkle all over with 1 tsp. paprika and 2 tsp. Diamond Crystal or 1¼ tsp. Morton kosher salt. Transfer to a large glass or ceramic bowl and pour in 1 cup buttermilk. Cover bowl and chill 15–30 minutes.
3. Meanwhile, whisk 1 cup rice flour, ½ cup yellow cornmeal, and 6 Tbsp. lemon-pepper seasoning in a shallow bowl to combine.
4. Whisk remaining 2 Tbsp. lemon-pepper seasoning and remaining 2 tsp. Diamond Crystal or 1¼ tsp. Morton kosher salt in a small bowl to combine. Set lemon-pepper salt aside.
5. Fit a medium Dutch oven or other heavy pot with thermometer; pour in vegetable oil to come about 1½" up sides (about 8 cups) and heat over medium until thermometer registers 325°. Dredge catfish in rice flour mixture, shaking off excess. Working in 2 batches and returning oil to 325° between batches, fry catfish, turning occasionally, until golden brown and crisp, 5–7 minutes per batch. Transfer fish to a wire rack set inside a rimmed baking sheet and let drain. Immediately sprinkle all over with reserved lemon-pepper salt.
6. Arrange catfish nuggets and celery sticks on a platter; serve with dip alongside.