Preheat your oven to 375°F (190°C) and lightly grease a 9x13 inch baking dish.

Par-boil the thinly sliced potatoes in lightly salted water for 5 minutes until tender but still firm, then drain well.

Heat 1 tablespoon of olive oil in a large skillet over medium-high heat and brown the ground beef, breaking it up and draining any excess fat.

Add the chopped onion to the beef and cook until softened, then stir in minced garlic, dried thyme, dried rosemary, and smoked paprika for one minute until fragrant. Season with salt and black pepper.

Whisk together beef broth and heavy cream in a separate small bowl.

Layer half of the par-boiled potato slices in the baking dish, then spread the seasoned ground beef mixture evenly over them and pour half of the broth and cream mixture on top.

Add the remaining potato slices, pour the rest of the broth and cream mixture over them, and sprinkle with shredded Gruyére cheese.

Bake for 35-45 minutes until the potatoes are tender and the cheese is melted, bubbly, and golden brown.

Let the casserole rest for 5-10 minutes before serving, and garnish with fresh chopped parsley if desired.