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
- 1/8 teaspoon cayenne pepper
- Kosher salt and fresh ground black pepper, to taste
- 3 lbs Yukon Gold Potatoes, thinly sliced
Instructions:
- Preheat the oven to 350 degrees Fahrenheit. Grease a 9×9 inch or not-deep 2-quart casserole dish.
- In a skillet over medium heat, melt the butter. Add the chopped onion and cook until soft. Then reduce the heat and add the minced 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 chopped 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 the 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 an additional 30-45 minutes, or until the potatoes are tender and the casserole is bubbly on the edges. Turn the broiler on for the last 1-2 minutes of cooking to brown the top. Sprinkle with fresh herbs before serving.