Start by seasoning the boneless chicken breasts generously with salt, pepper, and a sprinkle of your chopped fresh herbs. Let the seasoned chicken rest for about 10 minutes at room temperature.

In a large skillet over medium heat, cook thick-cut bacon strips until they are crispy, which should take around 6-8 minutes. Transfer the bacon to a plate lined with paper towels to drain the grease, reserving about 1 tablespoon of the bacon fat in the skillet.

Using the reserved bacon fat, place the seasoned chicken breasts in the skillet. Cook for 6-7 minutes on each side, or until golden brown and reaches an internal temperature of 165°F. Allow the chicken to rest for 5 minutes before slicing.

In a medium bowl, combine mayonnaise with minced garlic and finely chopped fresh herbs. Stir until smooth and season with salt and pepper to taste.

Toast slices of sourdough bread in a toaster or on a griddle until golden brown and crispy.

Spread the homemade herb mayo on one side of each slice of toasted sourdough. Layer with lettuce, tomato slices, chicken, and bacon. Top with the remaining slice of bread, mayo-side down, and serve immediately.