Step 1

Preheat the oven to 400°F (200°C). Grease a 12-cup muffin tin with nonstick spray. Line a baking sheet with parchment paper.

Step 2

Unroll the puff pastry and use a 4-inch (10 cm) round cutter to cut out 24 circles.

Step 3

Place half of the circles into the cavities of the prepared muffin tin. Place the remaining 12 circles on the prepared baking sheet and refrigerate until ready to bake.

Step 4

Heat the grapeseed oil in a medium saucepan over medium heat. Add the onion, celery root, and carrots and cook until tender, about 10 minutes. Add the parsnip, sweet potato, and flour and stir to coat the vegetables with the flour.

Step 5

Add the vegetable stock, thyme, and salt. Bring to a boil, then reduce the heat to medium and simmer until the sweet potatoes are tender, about 10 minutes.

Step 6

Scoop a heaping tablespoon of filling into each puff pastry cup. Top with the remaining puff pastry circles, crimping the edges and pressing to fit inside each muffin cup. Brush the top of the pastry with the beaten egg.

Step 7

Bake until golden brown, 20–25 minutes. Let cool for about 5 minutes before serving.

Step 8

Enjoy!