Start by pounding the chicken breasts to ¾ inch thickness using a meat mallet or rolling pin.
In a bowl, mix together the olive oil, ranch dressing, Worcestershire sauce, vinegar, lemon juice, minced garlic, and pepper to create the marinade.
Pour the marinade over the chicken, cover, and refrigerate for 2-3 hours or overnight.
Preheat the grill to medium-high heat.
Remove the chicken from the marinade and discard any excess marinade.
Grill the chicken for 12-15 minutes or until fully cooked, flipping once halfway through.
While the chicken is grilling, prepare the ranch spread and Parmesan crumb topping.
For the ranch spread, mix grated Parmesan and ranch dressing in a bowl and set aside.
For the Parmesan crumb topping, mix together the panko bread crumbs, garlic salt, shredded Parmesan, and melted butter in a separate bowl. The mixture should be evenly moistened.
Preheat the broiler.
Transfer the cooked chicken to an oven-safe casserole dish.
Spread 2 tablespoons of ranch spread on top of each chicken breast, followed by the shredded provolone and Parmesan crumb topping.
Place the casserole dish under the broiler and cook until the cheese has melted and the crumb topping begins to turn light brown.
Serve immediately.