Cook the pasta according to package instructions until al dente. Drain and rinse with cold water to stop the cooking process and cool it down. This helps keep the pasta firm and perfect for salads.
Rub the chicken breasts with olive oil, garlic powder, salt, pepper, and lemon zest. Make sure the seasoning coats evenly so every bite is flavorful. Let it sit for a few minutes before grilling.
Place the chicken on a preheated grill or grill pan. Cook for about 5–7 minutes per side until fully cooked and slightly charred. Let it rest before slicing to keep the juices intact.
In a large bowl, combine the cooled pasta and chopped romaine lettuce. Toss gently so the lettuce stays crisp and doesn’t bruise. This forms the fresh base of your salad.
Pour in the Caesar dressing and lemon juice, then mix until everything is well coated. Add Dijon mustard if using for an extra punch of flavor. The dressing should lightly coat all ingredients without being too heavy.
Slice the grilled chicken and place it over the pasta mixture. Add grated Parmesan cheese and croutons on top. Toss lightly or leave layered for a more presentable look.
Let the salad sit in the fridge for 10–15 minutes before serving. This helps the flavors blend beautifully. Serve chilled or slightly cool for the best taste.