Preheat your oven to 350°F (175°C).
In a large skillet, heat the olive oil over medium heat. Add the chopped onions and minced garlic, sautéing until the onions are translucent, about 5 minutes.
Add the ground beef to the skillet, cooking until browned. Drain any excess fat.
Stir in the diced tomatoes, salt, pepper, paprika, and oregano. Let it simmer for about 5 minutes.
In a baking dish, layer half of the sliced potatoes at the bottom.
Spread half of the beef mixture over the potatoes. Then, spread half of the sour cream and half of the shredded cheddar cheese on top.
Repeat the layers with the remaining potatoes, beef mixture, sour cream, and cheese.
Cover the baking dish with aluminum foil and bake in the preheated oven for 30 minutes.
Remove the foil and bake for an additional 20 minutes, or until the potatoes are tender and the top is golden brown.
Let it cool for a few minutes before serving.