Prep the chicken. Pat the chicken dry.
Rub with olive oil, salt, pepper, garlic powder, smoked paprika, and lemon juice. Let it sit at room temperature for 15 minutes while you heat the grill or grill pan.
Make the croutons. Toss the bread cubes with olive oil, melted butter, garlic powder, and salt. Spread on a baking sheet and bake at 375°F (190°C) for 10–12 minutes, tossing once, until golden and crisp.
Cool on the sheet.
Heat the grill. Preheat a grill or grill pan over medium-high heat. Oil the grates lightly to prevent sticking.
Grill the chicken. Cook the chicken 5–6 minutes per side, or until the internal temperature reaches 165°F (74°C). Let it rest for 5–7 minutes, then slice across the grain into strips.
Make the dressing. In a small bowl, whisk egg yolk (or mayo), anchovy, garlic, Dijon, and lemon juice.
Slowly drizzle in olive oil while whisking until slightly thick and glossy. Stir in Parmesan. Season with salt and plenty of black pepper.
If it’s too thick, whisk in a teaspoon of water.
Prep the lettuce. Wash and thoroughly dry the romaine. Moisture makes dressing slide off and turns the salad soggy. Chill the lettuce in the fridge for extra crunch.
Toss the salad. In a large bowl, combine romaine, half the croutons, and a few tablespoons of dressing.
Toss gently to coat. Add more dressing as needed; you want light, even coverage, not a heavy pour.
Finish and serve. Top with sliced grilled chicken, remaining croutons, and Parmesan. Add a squeeze of lemon and a final crack of black pepper.
Serve immediately.