Preheat your oven to 375°F (190°C).
Peel and slice the potatoes thinly.
In a skillet, melt butter and sauté onions and garlic until soft.
In a bowl, mix sour cream, milk, salt, pepper, and paprika.
Layer half of the potatoes in a greased baking dish.
Spread half of the onion mixture over the potatoes.
Pour half of the sour cream mixture over the onions.
Repeat the layers with the remaining ingredients.
Top with shredded cheese.
Bake for 45-60 minutes until golden and bubbly.