Ingredients
1 package (17.3 ounces) frozen puff pastry, thawed2 pounds boneless skinless chicken breasts, cut into 1-inch pieces1 teaspoon salt, divided 1 teaspoon pepper, divided 4 tablespoons butter, divided 1 large onion, chopped2 garlic cloves, minced1 teaspoon minced fresh thyme or 1/4 teaspoon dried thyme1 teaspoon minced fresh sage or 1/4 teaspoon rubbed sage1/2 cup all-purpose flour1-1/2 cups chicken broth1 cup plus 1 tablespoon half-and-half cream, divided2 cups frozen mixed vegetables (about 10 ounces)1 tablespoon lemon juice1 large egg yolk
Preparation
Preheat oven to 400°. On a lightly floured surface, roll each pastry sheet into a 12x10-in. rectangle. Cut 1 sheet crosswise into six 2-in. strips; cut remaining sheet lengthwise into five 2-in. strips. On a baking sheet, closely weave strips to make a 12x10-in. lattice. Freeze while making filling.
Toss chicken with 1/2 teaspoon each salt and pepper. In a large skillet, heat 1 tablespoon butter over medium-high heat; saute chicken until browned, 5-7 minutes. Remove from pan.
In same skillet, heat remaining butter over medium-high heat; saute onion until tender, 5-7 minutes. Stir in garlic and herbs; cook 1 minute. Stir in flour until blended; cook and stir 1 minute. Gradually stir in broth and 1 cup cream. Bring to a boil, stirring constantly; cook and stir until thickened, about 2 minutes.
Stir in vegetables, lemon juice, chicken and the remaining salt and pepper; return to a boil. Transfer to a greased 2-1/2-qt. oblong baking dish. Top with lattice, trimming to fit.
Whisk together egg yolk and remaining cream; brush over pastry. Bake, uncovered, until filling is bubbly and pastry is golden brown, 45-55 minutes. Cover loosely with foil if pastry starts getting too dark. Let stand 15 minutes before serving.
