1. Preheat oven to 375°F (190°C) and grease a baking dish.
2. Brown ground beef in a skillet with onion and garlic. Season with salt and pepper. Drain excess fat.
3. In the same skillet, melt butter and whisk in flour to make a roux. Gradually add heavy cream and beef broth, stirring until smooth and thickened.
4. Layer half of the potatoes in the baking dish, followed by half the beef mixture and half the cheese. Repeat the layers.
5. Pour the cream sauce over the top. Cover with foil and bake for 30 minutes.
6. Remove foil and bake for another 15-20 minutes, until cheese is golden and bubbly.
7. Garnish with parsley before serving.