Buttermilk Fried Chicken Fingers

In a wide, shallow bowl, combine buttermilk, milk, onion, jalapeño, salt, and Tabasco. Add chicken, cover, and refrigerate for 24 hours. Preheat oven to 250 °F. Set cooling racks over rimmed baking sheets. In a large bowl, combine the flour, granulated garlic, onion powder, thyme, sage, paprika, cayenne, salt, and pepper. In a large pot, pour in enough oil to come up to 2 inches. Set over medium-high heat until oil registers 350 °F on a deep-fry thermometer. Working in batches of 4 to 5 pieces, remove chicken from marinade, shaking to remove any vegetables and excess liquid, and dredge in the seasoned flour. Fry chicken pieces, turning once, until golden and cooked through, 6 to 7 minutes total per batch. Transfer chicken to wire racks and warm in oven while frying remaining batches. Serve chicken fingers with ranch dressing, if desired.