• 1 puff pastry sheet (half of a 17.3-ounce package)
• 1 1/2 pounds beef tenderloin , cut into 1-inch pieces
• 3/4 pound lamb kidneys or veal kidneys , cleaned, halved, vein removed, and cut into 1-inch pieces
• Salt and freshly ground pepper
• 2 Tbsp. canola oil
• 1 shallot , minced
• 1 carrot , finely chopped
• 1 celery stalk , finely chopped
• 2 Tbsp. all-purpose flour
• 2 cups good-quality beef stock , preferably homemade
• 3 Tbsp. unsalted butter , cold and cut into pieces
• 1 tsp. chopped fresh thyme

Note: We suggest using store-bought puff pastry for convenience, but you can also use chef Cathal's recipe.

Preheat oven to 400°. Line a large baking sheet with parchment. Cut puff pastry into six disks; arrange on sheet. Bake in upper third of oven until golden, 5 to 8 minutes. Cool on a wire rack.

Season beef and kidneys with salt and pepper. Heat a large, heavy skillet over medium-high heat; add oil. Working in 2 to 3 batches, sauté meat, turning occasionally, until just browned. Cook each batch 5 to 8 minutes; remove with a slotted spoon and set aside. Reduce heat to medium; add shallot, carrot, and celery to skillet. Sauté until vegetables are tender, stirring frequently, about 6 minutes. Stir in flour and cook, stirring constantly, 1 minute. Return meat to pan, and slowly stir in stock. Bring to a boil, stirring frequently, then stir in butter. Season with salt and pepper; add thyme.

To serve, divide stew among 6 bowls and top each with a puff pastry disk.

Chef Armstrong recommends pairing this dish with a Bordeaux.