Start by marinating the chicken. In a large bowl, combine the chicken with buttermilk. Cover and refrigerate for at least 1 hour (or overnight for deeper flavour). This step tenderizes the chicken and ensures juicy meat.
While the chicken marinates, prepare the slaw. In a medium bowl, mix shredded cabbage, carrots, and red onion. In a small bowl, whisk lime juice, vinegar, sugar, salt, and pepper. Pour the dressing over the vegetables, toss to coat, and refrigerate to let the flavours meld.
Prepare the sauce. Heat olive oil in a small saucepan over medium heat. Add minced garlic and sauté until fragrant. Stir in tomato sauce, chicken broth, ketchup, Worcestershire sauce, cumin, oregano, salt, and pepper. Simmer for 10 minutes, stirring occasionally. Set aside.
In a large bowl, mix flour, cornstarch, garlic powder, onion powder, paprika, cumin, salt, black pepper, and cayenne (if using). This combination creates a crispy and flavourful coating.
Remove the chicken from the buttermilk, allowing excess to drip off. Coat each piece thoroughly in the flour mixture, pressing the coating onto the chicken to ensure it adheres. Place the coated chicken on a wire rack to rest for 10 minutes. This helps the coating stick during frying.
Heat vegetable oil in a deep skillet or fryer to 350°F (175°C). Carefully fry the chicken pieces in batches, avoiding overcrowding. Cook for 12–15 minutes, turning occasionally, until golden brown and cooked through (internal temperature of 165°F or 74°C). Drain on paper towels.
Prepare the tajadas by frying thin slices of green banana or plantain in the same hot oil until golden and crispy. Drain and sprinkle with a pinch of salt.
Reheat the sauce gently over low heat. Adjust seasoning if necessary.
Assemble the dish by placing fried chicken on a platter, accompanied by a generous portion of cabbage slaw and a side of tajadas. Drizzle the warm sauce over the chicken or serve it on the side for dipping.
Garnish with lime wedges for an extra burst of flavour. Serve immediately while the chicken is hot and crispy. Encourage diners to enjoy the dish with their hands for an authentic experience.