Whisk together all of the ingredients for the ranch dressing until smooth and creamy. Taste and adjust the seasonings to your preference. Set aside.
Prepare the Croutons
In a small skillet, melt the butter over medium heat. Add the extra virgin olive oil and the chopped baguette. Cook for 3-5 minutes or until the bread is warm and toasted. Turn off the heat and transfer the toasted croutons to a bowl.
Prepare the Poached Chicken:
Place the chicken breasts in a shallow pan (a wide sauté pan works great for this) and season the breasts with salt. Add the peppercorns, bay leaves, and thyme. Place a crushed garlic clove on top of each chicken breast. Fill the pan with water until it reaches about the halfway point of the chicken breasts.
Bring the water to a boil and then turn the heat to medium for 5 minutes. Turn off the heat and cover the pan for 20 minutes. Test the temperature after 20 minutes. Once the chicken reaches 165ºF, transfer the breasts to a cutting board and thinly slice cross-wise.
Prepare the Salad:
Toss the romaine with the cucumber, radishes, and tomatoes. Drizzle with a teaspoon of extra virgin olive oil, if desired and a sprinkle of salt and pepper.
To Serve:
Divide the salad between blows and arrange the sliced chicken, avocado, and croutons on top. Serve with the ranch dressing. Enjoy!