In a large mixing bowl, combine 1 ½ cups of buttermilk, ½ cup of pickle juice (or white distilled vinegar), and 1 tablespoon of hot sauce. Whisk until well combined. Add the chicken tenders to the marinade, ensuring they are fully submerged. Cover and refrigerate for at least 2 hours, or overnight for the best flavor.
In another bowl, mix together the all-purpose flour, cornstarch, baking powder, garlic granules, onion granules, paprika, coarse salt, and ground black pepper. Whisk well to combine all the dry ingredients evenly.
In a separate bowl, beat the four large eggs with ½ cup of buttermilk until smooth. Remove the chicken tenders from the marinade, allowing excess liquid to drip off. Dip each tender into the egg mixture, then into the flour mixture, ensuring they are well coated. Repeat this process for an extra crispy texture.
In a Dutch oven or deep frying pot, heat oil over medium-high heat until it reaches 350°F (175°C). Use a kitchen thermometer to monitor the temperature for optimal frying.
Carefully add the chicken tenders to the hot oil in batches, ensuring not to overcrowd the pot. Fry for about 4-6 minutes per side, or until they are golden brown and cooked through. The internal temperature should reach 165°F (74°C).
Once cooked, remove the chicken tenders from the oil using a slotted spoon or spider and place them on a wire rack to drain excess oil. Allow them to cool for a few minutes before serving.