Ingredients

• 0.25 cups butter
• 1 cup onion
• 3 cloves garlic , minced
• 0.25 cups all purpose flour
• 0.5 teaspoons salt
• 0.5 teaspoons ground black pepper
• 2.5 cups half and half
• 0.67 cups grated Parmesan cheese , plus more for garnish
• 1 tablespoon orcestershire sauce
• 1 tablespoon ijon mustard
• 2 teaspoons lemon zest
• 1 tablespoon lemon juice
• 2.5 pounds russet potatoes , peeled and sliced 1/8-inch thick
• chopped chives

Instructions

1. 1 Gather all ingredients. Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking dish.
2. 2 Melt butter in a saucepan over medium heat and cook onion and garlic until soft and translucent, about 6 minutes.
3. 3 Stir in flour, salt, and pepper. Cook and stir for 1 minute.
4. 4 Add half-and-half. Cook and stir until thickened and bubbly, about 4 minutes.
5. 5 Stir in Parmesan cheese, Worcestershire sauce, mustard, lemon zest and juice. Cook and stir until cheese is melted, about 1 minute.
6. 6 Arrange half of the potato slices in the prepared baking dish. Pour and spread half of the sauce over the potatoes. Repeat with remaining potatoes and remaining sauce. Cover with foil.
7. 7 Bake in the preheated oven for 45 minutes. Uncover and bake until potatoes are tender, 40 to 45 minutes. Let stand before serving, 10 minutes. Garnish with additional Parmesan cheese and chives.

Nutrition per serving