Remove roast from refrigerator; let stand at room temperature for 1 hour before roasting. Pat roast dry with paper towels. Sprinkle with 1 tablespoon salt and 2 teaspoons black pepper.

For sauce, combine beef stock, Cabernet Sauvignon and 1 tablespoon butter in a small saucepan. Bring to a boil; reduce heat. Simmer, uncovered, over low heat for 35 to 40 minutes or until reduced by half. Set aside until ready to serve.

For filling, heat remaining 2 tablespoons butter and 2 tablespoons vegetable oil in a 12-inch skillet over medium heat. Add shallots; cook for 3 to 4 minutes or until softened, stirring often. Add mushrooms; cook for 5 to 6 minutes or until softened, stirring occasionally. Remove skillet from heat; stir in sherry. Return to heat; cook over medium heat for 5 to 8 minutes or until liquid is evaporated, stirring occasionally. Stir in 1 tablespoon thyme, 1 teaspoon salt, and remaining 1 teaspoon pepper. Transfer to a small bowl; set aside to cool.

Preheat oven to 450°. Place a wire rack in a large rimmed baking pan; lightly spray with nonstick spray; set aside.

Heat remaining 2 tablespoons vegetable oil in the same skillet over high heat. Sear beef 1 minute on each side or until brown. Transfer beef to prepared wire rack in pan. Brush top of roast with 2 tablespoons jam. Set aside.

Roll out 1 puff pastry sheet to a 16x13-inch rectangle on a lightly floured surface. Spread the mushroom mixture lengthwise down center of puff pastry. Place roast, jam side down, on top of mushroom mixture. Brush bottom and sides of roast with remaining 2 tablespoons jam. Bring edges of pastry up and around roast to enclose roast in pastry. Trim off excess pastry; reserve trimmings. Brush edges of pastry with beaten egg; press together to seal.

Place pastry-wrapped beef, seam side down, on rack in pan. Slightly score pastry to allow steam to escape while cooking. Roll out pastry trimmings and remaining pastry sheet; cut out shapes, if desired. Attach cutouts to wrapped roast by brushing with egg. Lightly brush pastry-wrapped beef with remaining egg; sprinkle with remaining ⅛ teaspoon salt.

Roast pastry-wrapped beef for 10 minutes. Reduce oven temperature to 425 degrees. Roast for 25 to 30 minutes more or until an instant-read thermometer inserted into the center of the roast reaches 120 degrees for rare or 130 degrees for medium-rare. If necessary, loosely cover with foil during the last 15 minutes of roasting to prevent overbrowning. Transfer to serving platter; let stand for 10 minutes. Meanwhile, warm sauce. Garnish with additional fresh thyme, if desired. Serve with sauce.