Preheat oven to 425 degrees F. Coat a cooling rack with nonstick spray and place on a baking sheet; set aside.
In a large bowl, combine chicken, Ranch Seasoning and Salad Dressing Mix, cayenne pepper, 1/2 teaspoon salt and 1/2 teaspoon pepper; let sit for at least 30 minutes.
Working one at a time, dredge chicken in flour, dip into buttermilk mixture, then dredge in cornflake mixture, pressing to coat.
Place chicken in a single layer onto the prepared baking sheet and coat with nonstick spray.
Place into oven and bake until crisp and cooked through, about 13-15 minutes.
Serve immediately.
for the buttermilk mixture
In a medium bowl, whisk together buttermilk and egg.
for the cornflake mixture
In a large bowl, combine cornflake crumbs, Parmesan and canola oil; season with salt and pepper, to taste.