Beef Wellington

This is time consuming but so tasty. I tend to make this for birthdays and dinner parties.

• Ready In: 1 hr 30 mins
• Serves: 6-8

Ingredients

• 2 1⁄2 lbs beef tenderloin (have butcher clean tenderloin)
•  kosher  salt & freshly ground black pepper
•  extra virgin olive oil
• 1  packet  store-bought puff pastry, defrosted (17.5 oz.)
• 1⁄4 cup butter, melted
• 1 1⁄2 tablespoons  finely chopped fresh rosemary
•  coarse sea salt
• 2 (2 lb) bags fresh spinach
• 1  garlic clove
• 1  tablespoon butter
• 1⁄2 teaspoon ground nutmeg
• 2  cups  assorted  wild mushrooms, quartered
• 3  sprigs thyme, leaves
• 1  tablespoon butter
• 3  tablespoons flour
• 1  cup red wine
• 2  cups demi-glace (store-bought or homemade) or 2  cups  rich  veal stock (store-bought or homemade)
•  parchment paper

Directions

1. Preheat oven to 400?F.
2. Season tenderloin all over with salt and freshly ground black pepper. Heat a large skillet or roasting dish and add approximately 2 tablespoons of olive oil. Sear the tenderloin until it has a nice deep brown color all over it and then put it into the preheated oven to bake for 20-25 minutes or until medium and juices run pink.
3. Prepare the pastry by laying it out flat on a sheet tray. Using a pastry cutter, cut the sheet into 4x4 inch squares and separate slightly. Brush the pastry all over with the melted butter and then sprinkle liberally with the chopped rosemary and some coarse sea salt. Use a fork to pierce the pastry so it doesn't rise too much when cooking. Bake in the oven for 10-12 minutes or until slightly puffy and golden.
4. Meanwhile, prepare the spinach. Heat the olive oil and butter over high heat and then add the garlic. Add the spinach and then the nutmeg and cook until just wilted. Season with salt and pepper and then set aside. In a separate pan, cook mushrooms over high heat with chopped garlic, butter and thyme. Season with salt and pepper, set aside.
5. Once the tenderloin is cooked, remove from the oven and set the tenderloin aside to rest. Cover loosely with tented foil. Set the pan on a stove top and dust with flour. Deglaze (add) with wine and the stock scraping the bottom of the pan with a spoon to extract all the flavors. Reduce over medium heat until thick and syrupy.
6. Take puff pastry square and slice horizontally in half. To assemble lay bottom half of the puff pastry square on the plate. Heap a spoonful of spinach on one side of square, a serving of mushrooms on the other and top with a couple of thick slices of tenderloin. Spoon over the remaining tenderloin juice to cover the meat and drizzle around the plate. Finish with other slice of puff pastry.