If the chicken is raw, season it with salt and pepper and cook in a lightly oiled skillet over medium-high heat for 5 to 6 minutes per side, until it reaches 74°C (165°F) in the thickest part. Rest 5 minutes and dice.
Hard-boil the eggs: cover with cold water, bring to a boil over high heat, turn off the heat, cover and leave 11 minutes. Cool in ice water, peel and quarter.
Cook the bacon in a skillet over medium heat for 6 to 8 minutes, turning, until crisp. Drain on paper towel and crumble.
Whisk the oil, apple cider vinegar, Dijon and pepper for the dressing.
Arrange the chopped romaine in two wide bowls and lay the chicken, egg, bacon, diced avocado, halved tomatoes and cheese over it in rows.
Drizzle with the dressing at the table and toss just before eating.