Baked Marbled Mashed Potatoes

1 . Stage

Place white potatoes in a large pot and cover with salted water. Place sweet potatoes in a second pot and cover with salted water. Bring both pots to a boil. Reduce heat to medium-low and simmer, uncovered, until tender, about 25 minutes. Drain and set aside to cool in 2 separate bowls.

2 . Stage

Preheat the oven to 350 degrees F (175 degrees C).

3 . Stage

While potatoes are cooling, melt butter in a small pan over medium heat. Add shallots and cook until tender, about 5 minutes. Remove from the heat.

4 . Stage

Mash potatoes with a potato masher or ricer.

5 . Stage

Beat cream in a chilled glass or metal bowl with an electric mixer until soft peaks form. Whisk sour cream into whipped cream.

6 . Stage

Stir 1/2 of the shallot mixture into each bowl then gently fold in. Gently fold 1/2 of the cream mixture into each bowl. Divide salt, pepper, and nutmeg evenly between the two bowls. Taste and adjust seasoning.

7 . Stage

Place 1/2 of the sweet potato mixture in a 2-quart baking dish. Layer 1/2 of the white potato mixture on top. Repeat layers once more, then swirl with a spatula to create a marbled effect.

8 . Stage

Mix melted butter, bread crumbs, and parsley for topping together. Sprinkle topping mixture over potatoes.

9 . Stage

Bake in the preheated oven until topping is golden brown and potatoes are hot all the way through, 30 to 35 minutes.