In a large bowl, combine the buttermilk, garlic powder, onion powder, paprika, black pepper, and salt. Whisk until smooth.
Add the chicken tenderloins to the buttermilk mixture, making sure they're fully submerged. Cover and refrigerate for at least 1 hour (or overnight for more flavor).
In another bowl, mix together the flour, cornstarch, and baking powder. Stir well to combine.
Remove the chicken from the refrigerator. One piece at a time, allow the excess buttermilk to drip off, then dredge the chicken in the flour mixture, ensuring it’s evenly coated. Shake off any excess.
Heat about 1 inch of vegetable oil in a large skillet over medium-high heat until it reaches 350°F (175°C).
Carefully place the coated chicken tenders into the hot oil, cooking in batches to avoid overcrowding. Fry for about 4-6 minutes on each side, or until golden brown and cooked through (internal temperature should reach 165°F/75°C).
Using a slotted spoon, transfer the fried tenders to a paper towel-lined plate to drain excess oil.
Repeat the process with the remaining chicken tenders.
Notes
Serve with your favorite dipping sauce and garnish with fresh herbs.