In a mixing bowl, combine the flour and salt. Add the cold butter and mix until the mixture resembles coarse crumbs.

Gradually add cold water, mixing until the dough comes together. Wrap in plastic wrap and refrigerate for 30 minutes.

In a skillet, heat vegetable oil over medium heat. Add the onion and cook until translucent.

Add the ground beef, cooking until browned. Stir in potatoes, carrots, thyme, salt, and pepper. Cook until vegetables are tender. Let cool.

Preheat the oven to 400?F (200?C). Roll out the pastry dough on a floured surface to about 1/8 inch thick.

Cut out circles of dough, about 6 inches in diameter. Place a spoonful of filling on one half of each circle, fold over, and seal the edges with a fork.

Place the pasties on a baking sheet lined with parchment paper. Cut a small slit in the top of each pasty to allow steam to escape.

Bake in the preheated oven for 25-30 minutes or until golden brown.

Let the pasties cool slightly before serving. Enjoy warm with your favorite dipping sauce.