In a large bowl, combine buttermilk, garlic powder, onion powder, paprika, cayenne pepper, salt, and black pepper.
Add the chicken tenders to the marinade, ensuring they are fully submerged. Cover and refrigerate for at least 2 hours, or overnight for best results.
In a separate shallow dish, place the flour.
Remove the chicken from the marinade, allowing excess buttermilk to drip off, and dredge each tender in the flour, pressing lightly to adhere.
In a large skillet, heat the vegetable oil over medium-high heat until it reaches 350°F.
Carefully add the chicken tenders in batches, frying for about 5-7 minutes per side, or until golden brown and cooked through. Use a meat thermometer to ensure the internal temperature reaches 165°F.
Once cooked, transfer the tenders to a paper towel-lined plate to drain excess oil.
Drizzle hot sauce over the tenders while they are still hot.
To serve, place the chicken tenders on slices of white bread, top with pickles, and enjoy.