Ingredients

2 lbs russet potatoes, thinly sliced
1 onion, finely chopped
2 cups shredded cheddar cheese
1 cup shredded mozzarella
2 cups heavy cream
3 tbsp butter
2 tbsp all-purpose flour
1 tsp garlic powder
Salt and pepper to taste

Directions

Wash, peel, and slice potatoes thinly (about 1/8 inch thick). Finely chop the onion and set both aside.

In a saucepan over medium heat, melt the butter. Stir in the flour and cook for 1 minute to make a roux. Slowly whisk in the heavy cream until smooth and thickened, about 3–5 minutes. Add garlic powder, salt, and pepper.

Remove from heat and stir in 1½ cups cheddar and ½ cup mozzarella until melted.

Grease the inside of your slow cooker with butter or non-stick spray. Layer half of the potatoes, half of the onions, and pour half the cheese sauce on top. Repeat with remaining potatoes, onions, and sauce.

Sprinkle the remaining cheddar and mozzarella over the top.

Cover and cook on LOW for 4–5 hours (or HIGH for 2½–3 hours) until potatoes are tender and the sauce is bubbly.

Let the dish rest for 10–15 minutes before serving to allow the sauce to thicken. Garnish with fresh parsley or chives if desired.