Trim excess fat from the chicken breasts or thighs. Cut each piece into 3–4 strips about 1–1.5 inches wide to make tenders. Pat the pieces dry with paper towels.

Marinate

In a medium bowl combine 3 tablespoons buttermilk, 1 teaspoon kosher salt, 1 teaspoon black pepper and 1 teaspoon hot sauce (if using). Add the chicken strips and toss to coat. Cover and refrigerate for at least 20 minutes and up to 2 hours. The buttermilk tenderizes and adds moisture.

Breading

Make breading mixture

In a shallow dish or bowl combine 3 tablespoons all-purpose flour, 3 tablespoons panko breadcrumbs, 1 tablespoon cornstarch, 1 teaspoon paprika, 1 teaspoon garlic powder, 1/2 teaspoon onion powder, 1/2 teaspoon dried oregano, 1/2 teaspoon ground black pepper and 1 teaspoon kosher salt. Whisk together so the spices are evenly distributed.

Prepare dredge

In a second shallow bowl whisk together the large egg and 1 tablespoon milk (or water) until smooth. This egg wash helps the breading stick to the chicken.

Breading and Frying

Heat oil

Pour about 1 cup of vegetable oil into a heavy skillet (preferably cast iron) — just enough to reach about 1/2 inch depth. Heat over medium-high heat until shimmering and a thermometer reads 340–350°F (170–175°C). If you don't have a thermometer, test with a small breadcrumb: it should sizzle and brown in about 30–40 seconds.

Bread the chicken

Working with a few pieces at a time, remove chicken from the marinade, letting excess drip off. Dip each strip into the egg wash, then press into the flour/panko mixture, coating all sides. For an extra-crispy double coating, return the coated strip to the egg wash and again to the breading. Place breaded tenders on a wire rack or plate while you finish the rest.

Fry in batches

Carefully place 3–4 tenders (depending on pan size) into the hot oil without overcrowding. Fry for 3–4 minutes per side, turning once, until coating is golden brown and internal temperature reaches 165°F (74°C). Adjust heat as necessary to keep oil between 320–350°F to avoid over-browning. Total fry time per batch will be about 6–8 minutes.

Drain and rest

Use tongs to transfer cooked tenders to a wire rack set over a baking sheet or to paper towels to drain. Lightly season with a pinch of salt while still hot. Let rest 2–3 minutes before serving to let juices redistribute and coating set.

Finishing and Serving

Arrange tenders on a platter. Sprinkle with chopped parsley and serve with lemon wedges and your choice of dipping sauces (ranch, honey mustard, BBQ, or ketchup). For oven-baked option: preheat oven to 425°F (220°C), place breaded tenders on a parchment-lined sheet, spray lightly with oil, and bake 12–15 minutes, flipping once, until golden and cooked through.