Butterfly the chicken breasts and flatten (with a mallet) to an even thickness. Season lightly with salt/pepper.

Place pretzels into a food processor or blender and grind into coarse crumbs.

Prepare a dredging station: one dish with flour + garlic powder + onion powder, one with beaten egg, one with pretzel crumbs.

Coat each piece of chicken: dredge in flour mixture, then egg, then press into pretzel crumbs.

Heat oil (~¼ inch depth) in a skillet over medium heat. Fry chicken in batches ~3–4 min per side until golden and cooked through.

While chicken cooks, melt butter in a saucepan over medium. Whisk in the 2 tbsp flour and cook 1 minute. Gradually whisk in milk until smooth and thickened (3–5 min).

Stir in cheddar cheese, Dijon mustard, paprika, cayenne (if using). Season with salt and pepper. Remove from heat once smooth.

Plate the fried chicken, drizzle with the mustard cheddar sauce, then top with chopped parsley, red onion, and pickle bits if desired.

Serve with lemon wedges on the side.