1 1/2 pounds small new potatoes such as Red Bliss
2 large lemons
Extra-virgin olive oil for brushing on lemons, plus 1/4 cup
4 boneless chicken breast halves, skin on
1 tablespoon minced garlic
1 cup double-strength chicken stock, or 2 cups canned low-salt chicken broth boiled until reduced by half
1 teaspoon finely chopped fresh rosemary
1 tablespoon unsalted butter (optional)
1. Put the potatoes in a pot of salted cold water and bring to a boil. Cook until just tender, about 20 minutes. Drain and let cool, but do not peel. Cut in half and set aside.
2. Preheat the broiler. Cut a small slice off both ends of each lemon, then cut in half crosswise. Arrange the lemons, flesh side up, in a flameproof nonreactive baking dish, brush with olive oil, and season with salt and pepper.
3. Broil 6 inches or more from the heat until browned and soft, about 10 minutes. Let cool. Squeeze the lemon halves over a sieve suspended over a bowl. Push and stir the pulp through the sieve with a rubber spatula or wooden spoon.
4. Preheat the oven to 450°F. Season chicken with salt and pepper. Heat remaining 1/4 cup olive oil in ovenproof sauté pan over medium-high heat until hot. Add chicken, lower the heat to medium, and cook until browned about 5 min. Put in platter.
5. Return the pan to medium-high heat, add the potatoes, season with salt and pepper, and cook, stirring and tossing, until brown all over, about 5 minutes. Arrange the chicken breasts on top of the potatoes and place in the oven to reheat, 10 minutes.
6. When done, remove the chicken to a platter and put the pan with the potatoes over medium-high heat. Toss well so the pan juices are absorbed into the potatoes. Scrape the potatoes out of pan onto the platter around the chicken.
7. Return the pan to medium-high heat and add the garlic. Sauté briefly until light brown. Immediately add the reserved roasted lemon juice (this final flash of heat will cook off any residual acid flavor), stock, rosemary, and parsley.
8. Stir and scrape up all the browned bits that cling to the bottom and sides of the pan. Season to taste with salt and pepper. If the sauce appears a little too lemony for your palate, stir in the optional butter.
9. Pour the sauce over the chicken and potatoes and serve immediately.