Chicken pan juices, shallots, white wine, and tarragon become a velvety sauce when you add butter as a finishing touch.
1 1/2 pounds medium-thick asparagus
4 tablespoons extra-virgin olive oil, divided
3/4 teaspoon each kosher salt and pepper
1/2 teaspoon paprika
1/4 teaspoon garlic powder
4 boned, skinned chicken breast halves (8 oz. each)
3 tablespoons minced shallot (1 medium)
1/2 cup dry white wine
2 teaspoon chopped tarragon, plus some leaves for sprinkling
1 cup reduced-sodium chicken broth
1 teaspoon lemon juice
2 tablespoons cold unsalted butter
How to Make It
Preheat oven to 400° with a rack in top third of oven and a second one below it.
Trim ends from asparagus, then toss with 1 tbsp. olive oil on a rimmed baking sheet. Sprinkle with 1/4 tsp. each salt and pepper. Roast on lower rack until tender and lightly charred, 15 to 20 minutes.
Meanwhile, stir together remaining 1/2 tsp. each salt and pepper with the paprika and garlic powder. Rub chicken with 1 tbsp. oil and the spice rub.
Heat remaining 2 tbsp. oil in a large ovenproof pan over medium-high heat. Add chicken; cook until browned beneath, 4 minutes. Turn over, then bake on upper rack until cooked through, 8 to 10 minutes. Transfer to a platter; tent with foil.
Discard all but 11/2 tbsp. drippings from pan. Add shallot and cook over medium heat, stirring, until softened, 2 minutes. Increase heat to high, stir in wine and chopped tarragon; boil until liquid reduces by half. Add broth and juices from cooked chicken; boil until reduced to 1/3 cup, 10 minutes. Stir in lemon juice, remove from heat, and stir in butter. Set asparagus next to chicken. Pour sauce over chicken and sprinkle with tarragon leaves.