Caramelized Pears and Blue Cheese Tarts

Bahan-bahan (4 porsi)

• 1 sheet store bought frozen puff pastry (, thawed (25 cm x 25cm / 10" x 10"))
• 2 pears
• 2 tbsp unsalted butter
• 1/3 cup brown sugar (, lightly packed)
• Pinch of salt
• 1 egg (, lightly beaten)
• 1/3 to 1/2 cup crumbled blue cheese ((I used gorgonzola))
• 3 tbsp walnuts (, roughly chopped)