This rich and creamy gratin is a must-have for any holiday table!
3 tbsp. butter, for greasing pan and dotting on top of gratin
4 to 5 medium Yukon Gold potatoes, peeled
2 small sweet potatoes, peeled
2 parsnips, peeled
2 carrots, peeled
Salt and freshly cracked pepper, to taste
2 shallots, finely sliced or diced
1 sprig thyme, finely chopped
1 1/2 cups to 2 cups whipping cream (35%)
1 1/2 cups grated Parmesan cheese
Chopped parsley or thyme sprigs, for garnishing
Preheat oven to 375 degrees F.
Grease a 9-inch round baking dish with 1 tbsp. butter. (Alternatively, you could use an oval or rectangular baking dish, just adjust the amount of vegetables and the baking time as needed.)
Using a mandoline slicer or sharp knife, slice potatoes, sweet potatoes, parsnips and carrots into 1/8-inch thick slices.
Add vegetable slices, shallots, thyme, and salt and pepper to a large bowl. Toss to combine.
Layer vegetables in prepared baking dish, adjusting the top layer so it makes a decorative overlapping pattern.
Add 1 1/2 cups whipping cream. Press down on the vegetables. You should see the cream come up the sides of the pan but the vegetable do not need to be submerged. Add 1/2 cup more cream, if needed.
Sprinkle top of gratin with grated Parmesan cheese and dot with the remaining butter.
Cover the baking dish tightly with aluminum foil. Bake until vegetables are fork tender, about 1 hour and 15 minutes to 1 hour and 30 minutes, depending on how deep the dish is.
For golden brown top: Remove the foil. Heat broiler to high. Broil until top of gratin is golden brown, about 2 to 3 minutes.
Keep warm and let rest for 10 to 15 minutes before slicing. Garnish with chopped parsley or thyme sprigs.
Yield: 8 to 10 servings.