# Ingredient List:
→ Vegetables
01 - 2 lbs Yukon Gold or Russet potatoes, peeled and thinly sliced
02 - 1 medium yellow onion, thinly sliced
→ Dairy
03 - 2 cups shredded sharp cheddar cheese
04 - 1 cup shredded mozzarella cheese
05 - 2 cups whole milk
06 - 2 tbsp unsalted butter
07 - 2 tbsp all-purpose flour
→ Seasonings
08 - 1 tsp salt
09 - 1/2 tsp black pepper
10 - 1/2 tsp garlic powder
11 - 1/4 tsp paprika
# How To Make:
01 - Preheat oven to 375°F. Grease a 9x13-inch baking dish with butter or cooking spray.
02 - Melt butter in a medium saucepan over medium heat. Add flour and whisk continuously for 1 minute until combined and lightly golden.
03 - Gradually pour milk into the roux while whisking constantly to prevent lumps. Continue cooking for 3-4 minutes until sauce thickens slightly.
04 - Remove pan from heat. Stir in salt, black pepper, garlic powder, and half of the cheddar and mozzarella cheeses until completely melted and smooth.
05 - Spread half the potato slices in the prepared baking dish. Top with half the onion slices followed by half the cheese sauce. Repeat layering with remaining potatoes, onions, and sauce.
06 - Sprinkle remaining shredded cheddar and mozzarella cheeses evenly over the top layer. Dust with paprika.
07 - Cover baking dish tightly with aluminum foil. Bake for 40 minutes at 375°F.
08 - Remove foil and continue baking for 25-30 minutes until potatoes are tender throughout and the top achieves a golden brown color.
09 - Allow the dish to rest at room temperature for 10 minutes before portioning and serving.