1. Prepare the Beef

Season each medallion with salt and pepper.
Heat olive oil in a skillet and sear the beef on all sides, about 1 minute per side.
Remove from heat and brush all sides lightly with Dijon. Let cool completely.

2. Make the Mushroom Duxelles

In the same pan, melt butter.
Add chopped mushrooms, shallot, garlic, thyme, salt, and pepper.
Cook until all moisture evaporates and mixture becomes paste-like.
Let cool.

3. Assemble

Roll out the puff pastry and cut into squares large enough to wrap each piece of beef.
Layer like this:

1. Prosciutto slice (optional, helps keep things dry)

2. Spoonful of mushroom duxelles

3. Seared beef medallion

Wrap tightly in puff pastry. Seal edges.
Place seam-side down on a baking sheet.
Brush tops with egg wash.

4. Bake

• Preheat oven: 400°F (200°C)

• Bake: 18–22 minutes
  Cook until pastry is golden and internal beef temp is around 125–130°F (52–54°C) for medium-rare.

Tips for Perfect Results

• Let the beef cool before wrapping so the pastry doesn’t get soggy.

• Make ahead: assemble and refrigerate up to 24 hours before baking.

• For extra flavor: use a mix of mushroom types (cremini, shiitake, button).

If you want, I can also give you:

• A dipping sauce (red wine reduction, peppercorn cream, etc.)

• A budget version using ground beef

• An air fryer version