Cut the chicken breasts in half lengthwise to make 4 thinner cutlets. Add them to a large zip top bag along with Tony's chicken marinade. Turn the bag a few times so the chicken is fully coated, and let it sit for 30 minutes.
Meanwhile, add the dressing ingredients to a medium bowl and stir/whisk together until smooth. Taste and adjust as needed (e.g. add more lemon juice, Tony's seasoning, or garlic).
Prepare the salad ingredients (tear lettuce into bite-size pieces and add it to a large salad bowl, grate the parmesan cheese, and measure out the croutons).
Once the chicken has finished marinating, heat the olive oil in a large skillet over medium-high heat. Once the pan is hot, add the chicken pieces (remove the chicken from the bag and discard the leftover marinade) - this will ensure the chicken gets a nice sear. Cook for about 5 minutes/side or until the chicken is cooked through, then transfer to a plate.
While the chicken cools a bit, assemble the salad. Gradually drizzle on the dressing to taste. Toss and then top with the cooked chicken (slice it into strips first). If you have any dressing left over, it'll be good in the fridge in a covered container for a few days. Serve the salad immediately.