Ranch Herb Sauce
½ cup coarsely chopped fresh dill
½ cup coarsely chopped flat-leaf parsley
½ cup coarsely chopped chives (if your carrots have tops, you can chop them up and add a handful of them, too)
¼ cup (packed) fresh tarragon or small basil leaves
2 cloves garlic, crushed
Juice of 1 lemon (about 1/4 cup)
¼ cup EVOO
2 tbsp. butter or EVOO
2 carrots, peeled and finely diced
2 large shallots or 1 onion, chopped
1 cup orzo
3 containers (22 oz. each) chicken bone broth or stock
2 ½ to 3 cups rotisserie chicken, pulled or chopped into bite-size pieces
2 cups fresh or thawed frozen green peas
3 to 4 cups baby lettuces or greens of choice, torn or coarsely chopped (optional)
1 cup crème fraîche, for serving
For the sauce, in a food processor, pulse the herbs, garlic, and lemon juice until the herbs are finely chopped. With the machine running, stream in the EVOO until the sauce is smooth. Season with salt and pepper.
For the soup, heat a soup pot or medium Dutch oven over medium to medium-high. Add the butter. When the butter melts, add the carrots and shallots; season with salt and pepper. Cook, stirring often, until the vegetables soften, about 5 minutes. Add the orzo and cook, stirring often, until light golden, about 2 minutes. Stir in the broth and bring to a boil. Add the chicken and peas and cook until heated through, about 5 minutes.
Stir the herb sauce into the soup. Add the greens, if using, and stir until wilted. Divide the soup among bowls and top each with a generous dollop of crème fraîche.