Healthier Potatoes Au Gratin

Preheat the oven to 485ºF.

Swirl the sliced leeks in a large bowl of water and set aside.

Peel the potatoes and cut into 1/8-inch-thick rounds.

Heat a large saucepan over medium heat. Add the frozen cauliflower and the garlic. Season with salt and pepper. Cook until cauliflower softens, about 5-7 minutes. Turn off the heat. Puree the cauliflower and garlic with an immersion hand blender (or a food processor). Add the milk and nutmeg and stir to combine. Add 3/4 cup of the grated cheddar.

Arrange 1/3 of the sliced potatoes along the bottom of a casserole dish. Add 1/3 of the leeks. Season with salt and pepper. Using heaping spoonfuls, arrange 1/3 of the cauliflower-cheddar mixture over the potatoes and leeks. Repeat this process twice.

Sprinkle 1/4 cup of grated cheddar over the top. Cover the dish with aluminum foil and place in the oven. Cook for about 35 minutes. Test the potatoes in the center of the dish to see if all are fully cooked and easily pierced with a fork. If not, continue baking for another several minutes.

When potatoes are fork tender, remove the foil, sprinkle the remaining 1/4 cup of cheddar over the top, and place under the broiler. Remove from the oven when the top is bubbling and golden, after about 3 minutes. Top with fresh chopped chives and serve.