Ingredients
• 4 tablespoons butter
• 4 tablespoons flour
• 1 medium onion chopped
• 3–4 cloves garlic, minced
• 3 cups whole milk
• 1 tablespoon chopped fresh thyme
• 1 tablespoon chopped fresh parsley
• ⅛ teaspoon cayenne pepper
• Kosher salt and fresh ground black pepper to taste
• 3 lbs Yukon Gold Potatoes thinly sliced
Preparation
• Preheat oven to 350 degrees. Grease a 9×9 inch or not-deep 2-quart casserole dish.
• Melt the butter in a skillet over medium heat. Add the onion and cook until soft. Then reduce the heat and add the garlic, cooking for 1 minute while stirring constantly.
• Whisk in the flour and cook for 2 minutes. Slowly add the milk whisking to combine. Cook over low heat until thickened, whisking frequently. Do not let it boil.
• Whisk in about 2/3 of the thyme and parsley and all of the cayenne pepper. Season with kosher salt and fresh ground black pepper to taste.
• Layer 1/4 of the sliced potatoes in the bottom of a greased casserole dish. Pour 1/4 of the sauce over the top of the potatoes and spread it out with a spoon or spatula. Repeat the layers 3 more times ending with the cream sauce. Top with the remaining fresh herbs.
Cover the casserole with aluminum foil and bake for 45 minutes. Remove the foil and bake uncovered for 30-45 minutes or until the potatoes are tender and the casserole is bubbly on the edges. Turn the broiler on the last 1-2 minutes of cooking to brown the top. Sprinkle with fresh herbs.