For the ranch dressing: Whisk the buttermilk, mayonnaise, sour cream and chives together in a mixing bowl. Season with hot sauce and some salt and pepper. Cover with plastic wrap and refrigerate until ready to use.
For the chicken tenders: Whisk the buttermilk, hot sauce, 1 tablespoon salt and 1/4 teaspoon pepper together in a large mixing bowl.
Slice the chicken across the grain into long diagonals about 1/2-inch wide. (Depending on the size of the chicken breasts, you should yield 8 to 12 pieces.) Place the chicken in the mixing bowl with the buttermilk mixture. Turn to coat evenly. Cover the bowl with plastic wrap and refrigerate for 1 hour.
Meanwhile, fill a large Dutch oven halfway with canola oil and heat to 350 degrees F. While the oil is heating up, put the panko breadcrumbs in a large resealable plastic bag. Push any air out of the bag and seal tightly. Use the flat side of a meat mallet to lightly crush the breadcrumbs. Open the bag and add 2 tablespoons salt, 1/2 teaspoon pepper, the all-purpose flour and granulated garlic. Seal the bag and shake to combine.
After 1 hour, remove the chicken from the buttermilk. Use your hands to transfer the chicken from the marinade to the bag of seasoned flour, letting any excess marinade stay behind in the bowl. Seal the bag and shake until all of the chicken is evenly coated. Use your hands to transfer the chicken back into the bowl of marinade, tossing gently to coat. Add the chicken back to the seasoned flour, seal the bag and shake again to evenly coat the chicken. Transfer all of the breaded chicken, in a single layer, onto a rack over a baking sheet and let sit for 15 minutes.
Fry the breaded chicken pieces in batches in the hot oil until golden brown and cooked through, 3 to 5 minutes for each batch. Make sure that the oil comes back to temperature after each batch. Use a slotted spoon or tongs to transfer the cooked chicken onto a large plate lined with paper towels to absorb any excess oil. Season liberally with salt.
To assemble, lay out the tortillas on a clean work surface. Evenly distribute the lettuce, tomato slices, both cheeses and the chicken tenders on each tortilla. Top with 2 tablespoons of ranch dressing on each wrap and pickled jalapenos, if using. Fold the part of the tortilla that is closest to you over the filling tightly. Fold over both sides of the tortilla and roll over tightly into a large burrito. Repeat this process with the remaining 3 wraps. Serve whole or cut in half on a bias. Serve immediately with the remaining ranch dressing on the side.