Using a frying pan, cook the chicken over medium heat until it is cooked through. Don’t roast it, just make sure it is cooked. While the chicken is cooking, dice onion, celery and bell pepper into small pieces and put them in a small bowl.
Cut the lettuce and tomatoes into thin slices and place in a separate bowl. Put almonds in a third small bowl.
In a large mixing bowl, combine eggs, mayonnaise, vinegar, mustard, lemon juice, olive oil black pepper and salt together with a whisk to make dressing for salad.
Add all prepared ingredients to the large mixing bowl with dressing and mix gently so that everything is coated with dressing evenly. Divide the salad into small serving bowls and serve.