In a large skillet, heat olive oil over medium heat. Add chopped onions and minced garlic, sautéing until onions are translucent. Add ground beef and cook until browned. Stir in diced potatoes, carrots, peas, salt, and pepper. Cook until vegetables are tender. Let cool.

Pastry Preparation

Make the Pastry

In a large bowl, combine flour and salt. Cut in cold butter until mixture resembles coarse crumbs. Stir in cold water, a tablespoon at a time, until dough comes together. Divide dough into 8 equal portions, shape into discs, and refrigerate for 30 minutes.

Assembling Pasties

Assemble the Pasties

Preheat the oven to 400°F (200°C). Roll out each disc of dough on a floured surface to about 1/8 inch thick. Place about 1/3 cup of the beef filling in the center of each circle. Fold the dough over to form a pocket and seal the edges with a fork. Place on a baking sheet.

Making the Gravy

Prepare the Gravy

In a saucepan, melt butter over medium heat. Add sliced onion and cook until caramelized. Stir in flour and cook for 1 minute. Gradually whisk in beef broth, cooking until thickened. Season with salt and pepper to taste.

Baking

Bake the Pasties

Bake the pasties in the preheated oven for 25-30 minutes or until golden brown. Serve hot with the brown onion gravy.