Prep time: 30 minutes
Cook time: 90-110 minutes

1. Preheat oven to 375°F (190°C).
2. In a large skillet, heat olive oil over medium heat. Add diced Ukrainian sausage and brown for 5-7 minutes. Add onions and sauté for 2-3 minutes until onions are cooked and translucent. Add chopped garlic and cook for an additional minute. Set the sausage and onions aside.
3. In the same skillet, melt a stick of butter. Slowly add 1/2 cup of flour while stirring constantly until the mixture comes together and is smooth.
4. Gradually stir in 4 cups of 2% milk, a little bit at a time, until you reach the desired consistency.
5. Add 1 tsp of salt, 1 tsp of garlic powder, and 1 tsp of onion powder. Stir well.
6. Optional: add 1 cup of grated aged white cheddar cheese and stir until melted and incorporated into the sauce.
7. In a large baking dish, spread a layer of the sauce on the bottom. Add a layer of sliced potatoes, then more sauce, and a layer of the sausage and onions. Repeat until all ingredients are used or the baking dish is full.
8. Finish with a layer of sauce on top and sprinkle the grated mozzarella and cheddar cheese on top.
9. Bake in the preheated oven for 30-40 minutes or until the cheese is golden brown and bubbly.
10. Let cool for a few minutes before serving. Enjoy!