Groentetas

Ingredients

• 2 medium sweet potato, peeled, sliced into ½” rounds
• 2 medium carrots, peeled, sliced into ½” rounds
• 1 medium parsnip, peeled, sliced into ½” rounds
• ¼ cup olive oil
• 2 tablespoons thyme leaves and extra for serving
• ½ teaspoon nutmeg
• ⅛ teaspoon freshly ground black pepper
• ½ teaspoon salt
• ¼ cup sugar
• ¼ cup water
• 450g frozen puff pastry, thawed
• 60g Gruyere, thinly sliced
• 1 large egg, lightly beaten