Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper.
- In a shallow bowl, combine the flour, garlic powder, onion powder, smoked paprika, salt, and pepper.
- Dip each chicken breast into the buttermilk, ensuring it’s fully coated. Then dredge the chicken in the seasoned flour mixture, pressing lightly to coat the chicken evenly.
- Heat the olive oil in a large skillet over medium-high heat. Once hot, add the chicken and cook for about 4-5 minutes on each side until golden brown and crispy.
- Once the chicken is cooked through (internal temperature should reach 165°F/75°C), remove from the skillet and place on the prepared baking sheet.
- If using cheese, place a slice of cheese on each piece of chicken and bake in the oven for 2-3 minutes, or until the cheese is melted and bubbly.
- While the chicken bakes, mix together the mayonnaise and Dijon mustard in a small bowl to create the creamy sauce.
- Toast the sandwich buns lightly in a separate pan or in the oven.
- Assemble the sandwiches by spreading the creamy sauce on both halves of the buns, then place the crispy chicken on the bottom bun. Add lettuce, tomato, and pickles if desired. Top with the other half of the bun.
- Serve immediately and enjoy!