Sweet Potato Gratin Stacks

Preheat the oven to 375°F. Lightly grease all 12 cups of a standard muffin pan with a small amount of the melted butter.
Slice the peeled sweet potatoes into even rounds about ⅛ inch thick using a mandoline slicer or sharp knife.
In a large mixing bowl, combine the remaining melted butter, heavy cream, garlic, thyme, salt, black pepper, and nutmeg. Mix with a wire whisk until combined.
Add the sweet potato slices and ½ cup of Parmesan cheese. Gently toss until evenly coated.
Stack the sweet potato slices evenly in the prepared muffin cups, pressing down gently. Fill each cup almost to the top.
Spoon any remaining cream mixture evenly over the stacks.
Sprinkle the remaining ¼ cup of Parmesan cheese over the tops.
Cover the muffin pan loosely with aluminum foil.
Bake for 25 minutes.
Remove the aluminum foil and bake for another 15 to 20 minutes, until the sweet potatoes are fork-tender and the tops are golden brown with slightly crispy edges.
Remove the muffin pan from the oven. Let the stacks rest in the pan for 5 to 10 minutes.
Carefully loosen the edges with a thin spatula and lift each stack from the muffin pan.
Transfer the stacks to a serving platter and sprinkle with chopped fresh parsley before serving.

Notes

Serving Size: 2 Sweet Potato Gratin Stacks

Tips and Tricks

Keep the Slices Even – Thin, evenly sliced sweet potatoes cook at the same rate and stack more neatly. A mandoline works great, but always use the safety guard.

Don't Overfill the Cups – Leave a little room at the top of each muffin cup so the cream mixture doesn't spill over during baking.

Use Freshly Grated Cheese – Freshly grated Parmesan melts better than the shelf-stable powdered variety and gives the tops a nicer texture.

Let Them Rest – Giving the stacks a few minutes to cool helps the layers stay together when you remove them from the muffin pan.

Make Ahead – Bake the stacks a day before serving, cool, and refrigerate in a covered container. Reheat before serving.

Storing and Reheating

Refrigerating – Store cooled sweet potato gratin stacks in an airtight container in the refrigerator for up to 3 to 4 days.

Reheating in the Oven – Place the stacks in a baking dish and cover loosely with aluminum foil. Reheat at 350°F for 10 to 15 minutes, or until heated through to 165°F. Remove the foil near the end to help the tops crisp up.

Reheating in the Microwave – Place one or two stacks on a microwave-safe plate. Heat in short intervals until heated through to 165°F. The edges will be softer than when reheated in the oven.

Freezing – Cool the baked stacks completely and freeze individually until firm. Transfer to an airtight freezer-safe container and freeze for up to 2 months. Thaw overnight in the refrigerator before reheating. The creamy layers may be slightly softer after freezing.

Nutrition

Calories: 303kcalCarbohydrates: 33gProtein: 7gFat: 16gSaturated Fat: 10gPolyunsaturated Fat: 1gMonounsaturated Fat: 4gTrans Fat: 0.2gCholesterol: 48mgSodium: 599mgPotassium: 564mgFiber: 5gSugar: 7gVitamin A: 22098IUVitamin C: 5mgCalcium: 175mgIron: 1mg