Prepare the chicken: If your grilled chicken breasts are cold from the fridge, slice them into 1/3"–1/2" strips and warm briefly in a hot skillet (1–2 minutes per side) with a teaspoon of olive oil over medium-high heat until heated through and lightly caramelized. Warming quickly keeps the exterior crisp and reactivates smoky flavors without drying the meat; slicing first increases surface area so it heats evenly.

Crisp the croutons (optional but recommended): Heat a small skillet over medium heat with 1 tsp olive oil. Add the whole-grain croutons and toss for 1–2 minutes until they sound crisp and smell toasty. Toasting (or re-crisping) brings back crunch and deepens the grain flavor — don't skip if the croutons have been sitting in a bag.

Make the yogurt Caesar dressing: In a medium bowl combine 1 cup Greek yogurt, 2 tbsp fresh lemon juice, 1 tsp Dijon mustard, the grated garlic clove, 3 tbsp extra-virgin olive oil, 3/4 tsp kosher salt and 1/2 tsp black pepper. Whisk vigorously to emulsify. Emulsifying (whisking oil into yogurt with mustard and acid) creates a silky texture that clings to the leaves like a classic Caesar even without egg.

Taste and balance the dressing: Adjust seasoning — if it tastes flat, add another 1/2 tbsp lemon juice; if too tart, add 1/2 tsp honey or sugar. Balancing acid and salt is crucial because yogurt is tangy but milder than raw egg yolk; the mustard and olive oil provide body and a hint of bite.

Tear and chill the romaine: With clean hands, tear the romaine into bite-sized pieces and spin or pat them very dry. Cold, dry lettuce holds dressing better and stays crunchy; excess water will dilute the dressing and make the salad soggy.

Assemble the salad: In a large mixing bowl add the chopped romaine and pour about two-thirds of the dressing over it. Toss gently but thoroughly — start with less dressing to avoid overdressing. Add the warm sliced chicken and toss once more so the chicken heats slightly and the dressing coats everything evenly.

Finish and serve: Transfer the dressed salad to a platter or individual bowls. Scatter the toasted croutons and Parmigiano-Reggiano shavings over the top. Serve the remaining dressing alongside for guests who want extra. Leaving some dressing aside preserves texture and lets each diner control creaminess.

Optional final flourish: Finish with a quick grind of fresh black pepper and a light drizzle (½ tsp) of good olive oil or a squeeze of lemon to brighten just before serving — small contrasts of acid and fat at the end make the flavors pop.