Soak the chicken tenders in buttermilk for a minimum of 30 minutes or up to 8 hours.
Preheat the oven to 425°F and place an empty sheet pan in the oven for 10 minutes.
In a large plate, mix the flour, cornmeal, panko breadcrumbs, salt, pepper, onion powder, garlic powder, and smoked paprika.
Remove each chicken tender from the buttermilk mixture and coat evenly with the flour mixture. Repeat with the remaining chicken.
Remove the sheet pan from the oven and add the butter. Wait 2-3 minutes until the butter is melted and spread it evenly over the bottom of the pan.
Place the coated chicken tenders in a single layer on the melted butter. Bake for 10 minutes, then flip and bake for 8 more minutes. Broil for 2-3 minutes or until the tops are crispy.
Serve hot and sprinkle with chopped parsley if desired.