01 -
Pat beef tenderloin steaks dry and season generously with salt and pepper.
02 -
Heat olive oil in a heavy-bottomed pan over medium-high heat. Sear steaks on all sides until browned, about 1–2 minutes per side. Transfer to a plate and let cool completely.
03 -
In the same pan, melt butter over medium heat. Add finely chopped mushrooms and cook, stirring often, until all moisture has evaporated and mixture is dry, 8–10 minutes. Season with salt and pepper and allow to cool.
04 -
Brush cooled steaks evenly with Dijon mustard on all sides.
05 -
On a lightly floured surface, cut puff pastry into two equal squares. Spread half the mushroom mixture in the center of each square, place a steak on top, and cover steaks with remaining mushrooms.
06 -
Fold pastry over steaks, pressing edges to seal tightly. Place wrapped steaks seam side down on a lined baking tray. Brush each pastry with beaten egg.
07 -
Preheat oven to 200°C. Bake Wellingtons for 18–22 minutes, until pastry is golden and internal temperature reaches desired doneness. Rest 5 minutes before serving.
08 -
In a bowl, whisk together sour cream, prepared horseradish, Dijon mustard, and lemon juice. Season with salt and pepper to taste. Chill until serving.
09 -
Slice Mini Beef Wellingtons and serve with creamy horseradish sauce. Garnish with fresh parsley and offer extra sauce on the side.