Cook the bacon: Place the bacon in a cold skillet, then turn heat to medium.
Cook until crisp, 8–10 minutes, flipping as needed. Transfer to a paper towel-lined plate. Once cool, crumble or chop into bite-size pieces.
Reserve 1 teaspoon bacon fat in the pan for extra flavor.
Season the chicken: Pat chicken dry with paper towels. Season both sides generously with salt and pepper. Optional: add a pinch of garlic powder and paprika for a savory crust.
Sear the chicken: Heat the reserved bacon fat and 1 tablespoon olive oil over medium-high.
Add chicken and cook 5–7 minutes per side, depending on thickness, until the internal temperature reaches 165°F (74°C). Rest on a cutting board for 5 minutes, then slice or cube.
Make the dressing: In a bowl, whisk mayonnaise, Parmesan, lemon juice, Dijon, garlic, and anchovy. Slowly drizzle in olive oil while whisking until smooth and creamy.
Season with salt and plenty of black pepper. Thin with a teaspoon of water or lemon juice if desired.
Prep the greens: Rinse and dry the romaine very well. Chop into bite-size pieces.
Wet lettuce waters down the dressing, so use a salad spinner or pat dry thoroughly.
Assemble the bowls: Divide romaine among bowls. Top with sliced chicken, crumbled bacon, Parmesan, cucumber, and avocado if using. Drizzle with dressing and finish with extra black pepper.
Toss or not: For even coating, toss the salad in a large bowl before serving.
If you prefer a composed look, leave it layered and let everyone mix at the table.