Place chicken breast tenders in a one gallon Ziploc bag. Add buttermilk. Seal bag, squeezing out as much air as possible and gently squish pieces around to coat evenly. Place in fridge to marinate for at least 1 hour (4 hours or more is best)
When ready to bake: Preheat oven to 350F and grease or line a baking sheet. In another gallon Ziploc bag crush cornflakes to about panko bread crumb size. Add remaining six ingredients listed. Seal bag and shake to mix.
Use tongs to transfer about 4 tenders at a time to the bag of crumb mix. Seal bag with air inside, shake to coat pieces, transfer coated pieces to baking sheet with tongs. Repeat in batches until all pieces are coated. NOTE: I patted the remaining loose crumb mix left in the bag onto the tops of the tenders to ensure a good crunch.
Place in oven and bake uncovered for 30 - 40 minutes, or until Fully cooked. Remove from oven, let cool 5 minutes, Serve with your favorite sides and enjoy! Goes great with bowtie alfredo!