# Components:
→ Vegetables
01 - 2.5 lbs russet or Yukon Gold potatoes, peeled and thinly sliced
02 - 1 small yellow onion, thinly sliced
→ Dairy
03 - 2 cups whole milk
04 - 1 cup heavy cream
05 - 2 cups sharp cheddar cheese, shredded
06 - 1 cup Gruyère or Monterey Jack cheese, shredded
07 - 4 tablespoons unsalted butter
→ Pantry & Spices
08 - 3 tablespoons all-purpose flour
09 - 1 teaspoon garlic powder
10 - 1 teaspoon salt, plus more to taste
11 - ½ teaspoon ground black pepper
12 - ¼ teaspoon smoked paprika
13 - Chopped fresh chives or parsley, for garnish (optional)
# Method:
01 - Preheat the oven to 375°F. Grease a 9x13-inch baking dish with butter.
02 - In a medium saucepan over medium heat, melt the butter. Whisk in the flour continuously for 1–2 minutes until bubbly and lightly cooked, without browning.
03 - Gradually whisk in the whole milk and heavy cream. Continue whisking until the mixture thickens, about 3–5 minutes.
04 - Stir in garlic powder, salt, ground black pepper, and smoked paprika. Remove the pan from heat.
05 - Add 1½ cups shredded sharp cheddar and ½ cup shredded Gruyère or Monterey Jack cheese. Stir until completely melted and smooth.
06 - Arrange half of the sliced potatoes evenly in the prepared baking dish. Top with half of the sliced onions.
07 - Pour half of the cheese sauce over the potatoes and onions. Repeat layering with remaining potatoes and onions, then cover with the rest of the cheese sauce.
08 - Sprinkle the remaining shredded cheddar and Gruyère cheeses evenly over the top layer.
09 - Cover the baking dish tightly with aluminum foil and bake for 45 minutes.
10 - Remove the foil and continue baking for an additional 25–30 minutes until the potatoes are tender and the surface is golden and bubbling.
11 - Allow the dish to rest for 10 minutes before garnishing with chopped chives or parsley and serving.
