Combine minced pork and beef with egg, salt, and pepper. Mix well.
Peel and thinly slice potatoes. Arrange in an oiled baking dish and season with salt.
Mix 4 tbsp mayonnaise or sour cream with 3 tbsp hot water, spices, and salt. Pour over potatoes.
Slice onion into half rings and spread over potatoes.
Add the meat mixture as the next layer.
Slice the tomato and arrange on top of the meat.
Make a crosshatch pattern with mayonnaise on top.
Sprinkle grated cheese over the casserole. Preheat oven to 200°C (392°F) and bake for 35-40 minutes until potatoes are soft and meat reaches 63°C (145°F) internal temperature. If cheese is browning too quickly, cover with foil.