Cheesy Potatoes Au Gratin

Ingredients:

• Cheese Sauce:
• 4 tbsp salted butter
• 1 yellow onion, diced
• 4–5 garlic cloves, minced
• ¼ cup all-purpose flour
• 4 cups half-and-half (room temp)
• 1 tbsp Herbs de Provence
• 1 tsp dried mustard powder
• 1 tsp salt (plus more for layering)
• ½ tsp black pepper
• 1 cup shredded sharp cheddar
• 1 cup shredded smoked Gouda
• 1 (5.3 oz) Boursin garlic & herb cheese
• Potatoes & Topping:
• Butter or spray for greasing
• 3 lbs Yukon gold potatoes, thinly sliced
• 1 cup shredded sharp cheddar
• 1 cup shredded Gouda

Instructions:

1. Preheat oven to 375°F and grease an 11-inch baking dish.
2. Sauté onions in butter for 5 minutes. Add garlic and cook 1 minute.
3. Whisk in flour and cook 1–2 minutes.
4. Slowly pour in half-and-half, whisking until thick and creamy.
5. Add Herbs de Provence, mustard, pepper, salt, then cheddar, smoked Gouda, and Boursin. Stir until smooth.
6. Layer one-third of the potatoes in the dish, sprinkle with salt, and pour one-third of the sauce on top. Repeat for 3 total layers.
7. Cover tightly with foil and bake 1 hour.
8. Remove foil, top with remaining cheddar & Gouda, and bake 20–30 minutes until golden and bubbly.
9. Rest 10–15 minutes before serving.