1. Begin by cutting the chicken breasts in half lengthwise to create four thinner pieces. In a large bowl, whisk together the pickle juice, milk, powdered sugar, garlic powder, onion powder, black pepper, salt, and smoked paprika. Add the chicken to the marinade, ensuring each piece is well-coated. Cover the bowl and refrigerate for at least 30 minutes, or up to 4 hours.

2. While the chicken is marinating, prepare the Honey Roasted BBQ Sauce by combining the mayonnaise, sweet BBQ sauce, honey, Dijon mustard, lemon juice, and smoked paprika in a bowl. Whisk until well-blended and refrigerate until ready to use.

3. Preheat your grill to medium heat. Remove the chicken from the marinade and discard any remaining liquid. Grill the chicken for about 15 minutes or until the internal temperature reaches 165°F, flipping occasionally. During the last minute of cooking, top each piece with a slice of cheese to melt slightly.

4. To assemble the sandwich, remove the tops from the multigrain buns. On the bottom half, layer green leaf lettuce and a slice of beefsteak tomato. Add a piece of grilled chicken with melted cheese and a slice of crispy bacon (broken in half). Spread Honey Roasted BBQ Sauce on the cut side of the top bun and place it on the sandwich. Serve immediately.