Heat 1/2 teaspoon oil in large nonstick skillet on medium-high heat until hot. Combine salt and 1/4 teaspoon pepper. Press evenly onto all surfaces of beef Tenderloin Roast. Place roast in skillet; brown evenly. Remove roast from skillet.
Heat oven to 425°F. Place mushrooms and shallot into food processor; pulse on and off about 10 times until finely chopped. Do not over process. Heat remaining 1/2 teaspoon oil in same skillet over medium-high heat until hot. Add mushrooms and shallot; cook 4 to 6 minutes until tender and all liquid is evaporated, stirring often. Add wine; cook 2 to 3 minutes until all liquid is evaporated. Stir in mustard, thyme, remaining 1/4 teaspoon pepper. Cook 2 to 3 minutes. Remove from skillet to medium bowl; cool.
Line rimmed baking sheet with aluminum foil and place in oven. Unfold pastry dough on lightly floured cutting board. Roll pastry out to 12 by 9-inch rectangle; lay dough with shortest edge toward you. Spread mushroom mixture onto pastry dough, leaving 1/2-inch border around edge of dough. Place roast in center of mushrooms. Fold pastry dough neatly around roast, stretching dough if necessary. Cut off excess pastry dough; press to seal overlapping edges. Remove baking sheet from oven and dust lightly with flour. Place pastry-wrapped roast, seam-side down, on baking sheet. Cut 4 (2-inch) vents in top of pastry.
Bake in 425°F oven 35 to 50 minutes or until golden brown and instant-read thermometer inserted into center of roast registers 135°F for medium rare; 150°F for medium. Transfer Beef Wellington to carving board. Let stand 10 minutes. (Temperature will continue to rise about 10°F to reach 145°F for medium rare; 160°F for medium.) Carve into slices and serve with your favorite vegetables.
Nutrition information per serving: 386 Calories; 153 kcal Calories from fat; 17 g Total Fat; 6 g Saturated Fat; 8 g Monounsaturated Fat; 119 mg Cholesterol; 584 mg Sodium; 9 g Total Carbohydrate; 1.2 g Dietary Fiber; 42 g Protein; 5.4 mg Iron; 10.4 mg Niacin; 1.1 mg Vitamin B6; 5.8 mcg Vitamin B12; 6.3 mg Zinc; 43.6 mcg Selenium; 103.1 mg Choline;