Chicken Wellington

Step 1
Heat olive oil and butter in a large skillet over medium heat. Season chicken breasts with salt and black pepper. Cook chicken in the hot oil until golden and almost cooked through, about 4 minutes per side. Transfer to a plate.

Step 2
Place onion, mushrooms, and garlic in the same skillet; cook and stir until mushrooms lose their moisture and onions are tender, about 5 minutes. Stir in parsley.

Step 3
Preheat oven to 375 degrees F (190 degrees C). Line a baking sheet with parchment paper.

Step 4
Roll out each puff pastry sheet into a 14-inch square on a floured work surface. Cut each sheet into 4 equal squares. Place a chicken breast in the center of each square.

Step 5
Combine cream cheese and Dijon mustard in a small bowl. Spread some of the cream cheese mixture over each chicken breast. Top each with 2 tablespoons of the mushroom mixture. Brush the edges of each square with water and wrap around the chicken. Place seam-side down on a baking sheet. Brush the tops with the beaten egg.

Step 6
Bake in the preheated oven until puffed and golden brown, about 20 minutes. Remove from oven and slice in half before serving.