1. Preheat the oven at 425°F. Grease a roasting pan with oil and set aside.
2. In a small bowl combine together egg and water to make egg wash. Set aside.
3. Place the beef tenderloin into the prepared roasting pan. Season with the black pepper.
4. Roast the tenderloin for 30 minutes in the oven at 425 degrees, or until a meat thermometer reads 130°F.
5. Cover the tenderloin with the foil and refrigerate the meat for 60 minutes to cool.
6. Reheat the oven to 425°F.
7. In a medium skillet heat the butter over medium-high heat.
8. Add in the mushrooms and onion and cook until the mushrooms are tender and all the liquid is evaporated, stirring often. Let the mushrooms cool.
9. Lightly flour the kitchen counter. Unfold one pasty sheet and roll it into a rectangle about 4 inches longer and 6 inches wider than the beef.
10. Brush the pastry sheet with the egg wash.
11. Spoon the mushroom mixture onto the pastry sheet to within one inch of the edges.
12. Place the beef in the center of the mushroom mixture, fold the pastry over the beef and press to seal.
13. Place the Wellington, seam-side down onto a baking sheet. Tuck the ends under to seal. Brush the pastry exterior with the egg wash.
14. Bake the Wellington for 25 minutes or until the pastry is golden brown and a meat thermometer reads 140°F.
15. Slice and serve Beef Wellington with red wine.
If you are arranging a gorgeous dinner party and want to impress your guests with something real delicate, then beef wellington could be a nice choice. You might have an idea, that preparing this at home is only a professional chef's job. No - you too can prepare this, when you watch the video and follow the necessary steps. So, go ahead!