Sauté the diced vegetables in a bit of butter. Next, sauté the ground beef and add concentrated tomato paste - spices - red wine - broth - Worcestershire sauce - water and the frozen peas. Let it simmer for about 20-30 minutes. Meanwhile, prepare the mashed potatoes: Peel and slice 5-6 baking potatoes. Boil the potatoes until tender and drain the water. Stir in about 3-4 tbsp crème fraîche and about 40-50 grams of cold butter. Season with salt and pepper to taste. Place the meat sauce at the bottom of an ovenproof dish and top with the mashed potatoes. Sprinkle with grated parmesan cheese and score a pattern with a fork. Place the dish in the oven for about 30-40 minutes at 180° until the surface is golden. Let the dish rest for 10 minutes before serving.