Preheat your oven to 400°F (200°C).

In a large mixing bowl, combine the butternut squash, carrots, parsnips, sweet potatoes, and Brussels sprouts. Drizzle with olive oil, then sprinkle in salt, pepper, fresh thyme, and rosemary. Toss everything together until the vegetables are evenly coated.

Spread the seasoned vegetable mixture onto a baking sheet in a single layer. Roast for 25-30 minutes until fork-tender and slightly caramelized.

Heat a tablespoon of butter in a medium saucepan over medium heat. Add chopped onion and minced garlic, sautéing for about 5 minutes until onion is translucent.

Sprinkle the all-purpose flour over the sautéed onion and garlic mixture. Stir for 1-2 minutes to form a roux.

Gradually whisk in the vegetable broth, cooking for 3-4 minutes until it thickens to a creamy consistency.

Pour in the heavy cream and stir to combine. Gently fold in the roasted vegetables.

Roll out the thawed puff pastry on a lightly floured surface, cut into rounds larger than your pie bowls.

Fill each pie bowl with the vegetable mixture, top with puff pastry rounds, and press edges to seal.

Brush the tops of the pastry with beaten egg for a golden finish.

Bake in the oven for 20-25 minutes until the pastry is puffed and golden brown.

Allow to cool slightly before serving warm.