Heat oil in a large pan over medium-high heat. Add the beef and cook for 5-7 minutes, breaking it up with a spoon as it cooks, until browned.
Add the grated potatoes, diced onion, herbs Provence, mint, and cumin to taste. Cook over medium heat for 5-7 minutes, stirring occasionally, until the potatoes are softened. Season with salt and pepper to taste.
In a bowl, mix the yogurt, milk, oil, and eggs until well combined.
Preheat oven to 180°C (350°F). Oil a baking tray.
Lay 2 sheets of pastry on the prepared tray. Spread half the meat mixture over the top.
Spread roughly 2/5 of the yogurt mixture over the meat. Scatter a few torn pieces of pastry over the yogurt. If using sheep cheese, sprinkle some crumbled cheese on top. Lay 1 sheet of pastry on top.
Spread the remaining meat mixture over the pastry.
Spread roughly 2/5 of the yogurt mixture over the meat. Scatter a few torn pieces of pastry over the yogurt. If using sheep cheese, sprinkle some crumbled cheese on top. Lay 1 final sheet of pastry on top.
Pour the remaining yogurt mixture over the top layer.
Bake for 30-35 minutes at 180°C (350°F) until the top is golden brown and crispy.