Easy & Juicy Bake Beef Wellington for a Mouthwatering

Ingredients

• 2 lb (900 g) beef tenderloin (filet mignon)
• Salt, to taste
• Black pepper, to taste
• 2 tablespoons (30 ml) vegetable oil
• 12 oz (340 g) cremini or button mushrooms, finely chopped
• 2 tablespoons (30 g) unsalted butter
• 2 cloves garlic, minced
• 1 teaspoon fresh thyme, chopped
• 6 oz (170 g) prosciutto, thinly sliced
• 1 tablespoon (15 ml) Dijon mustard
• 1 sheet (about 14 oz, 400 g) puff pastry, thawed if frozen
• 1 large egg, beaten (for egg wash)
• Flour, for dusting