Thoroughly wash the head of romaine lettuce, drain well, and cut the leaves into large pieces. Cut the half avocado into equal slices. Make the dressing by stirring the organic Greek yogurt, olive oil, Dijon mustard, and a splash of lemon juice together smoothly in a large bowl.
Bring a small pot of water to a boil and cook the free-range egg for six minutes until soft-boiled. Immediately shock the egg under cold running water after cooking. At the same time, pan-fry the organic chicken breast in a skillet over medium-high heat until golden brown and cooked through on both sides.
Let the cooked chicken breast rest briefly on a cutting board and then slice the meat. Peel the cooled free-range egg and cut it lengthwise in half. Add the pieces of romaine lettuce to the bowl with dressing and toss everything together well.
Distribute the dressed salad over a plate. Lay the sliced chicken breast and the sliced avocado on top of the salad. Place the two halves of the soft-boiled free-range egg on top of the dish and serve immediately.