Mini Beef Wellingtons

Combine a mixture of sautéed mushrooms, sherry wine, caramelized onion, melted butter, and chopped parsley in a large skillet over medium heat; cook and stir until all the liquid has evaporated and mushrooms are nicely caramelized, approximately 15 to 20 minutes. Set aside to cool, then spread a layer of the mushroom mixture evenly over each piece of tenderloin.

Cut each partially thawed puff pastry sheet into 3 equal-sized rectangles, resulting in a total of 6 pieces of puff pastry. Roll out each puff pastry rectangle to about 1/4-inch thickness and position the beef in the center; fold up the edges and seal all the boundaries, ensuring the seams are not too bulky. Place on a baking sheet, cover with plastic wrap, and refrigerate until 35 minutes prior to serving time.

Preheat the oven to a high temperature of 425 degrees Fahrenheit (220 degrees Celsius).

Bake the beef Wellingtons in the preheated oven for 25 minutes. An instant-read thermometer inserted into the center should read 130 degrees Fahrenheit (54 degrees Celsius) for medium rare. Allow to rest for 5 minutes before serving