When I came across this recipe, I knew right away that it was going to be delicious. And let me tell you, it’s more than delicious, it’s deeply satisfying as well. I really love root vegetables; I especially like how creamy their texture is when cooked. Other than the lovely creaminess of the vegetables, I think there are two keys to this gratin’s success, the first being the garlic steeped milk and the other being fresh nutmeg. Whatever you do, don’t skip those steps. I mean it! Fresh nutmeg! I made the gratin in a dutch oven, even though the recipe specified a much smaller baking dish, and I was happy I did since I didn’t measure my vegetables and ended up making quite a bit more than I should have. Which was a good thing in the end, since Mick and I annihilated the entire pot in a very short period of time.
Autumn Root Vegetable Gratin
1 ½ cups whole milk ( I used 2% and some cream)
2 cloves garlic
Pinch freshly grated nutmeg
2 tbsp extra virgin olive oil
¾ pound butternut squash
¾ pound white potatoes
½ pound parsnips
Salt and pepper
¼ tsp chopped fresh thyme leaves – optional
¼ tsp finely chopped fresh rosemary – optional
1 cup grated Gruyère
1 cup grated Pecorino
Heat the oven to 400° F. Put the milk in a small heavy saucepan and peel and smash one of the garlic cloves. Add it to the milk and then heat the milk over low heat until it just starts to bubble at the edges. Remove from the heat, add the nutmeg and let steep while you continue with the recipe.
Peel the second garlic clove, cut it in half and rub the cut side around the inside of a 6-cup baking dish no more than 2 inches deep. Rub 1 tablespoon of the oil all over the inside of the dish.
Peel the squash, potatoes and parsnips and cut them into very thin slices (1/8-inch thick). If you have a mandoline, now’s the time to use it.
Layer the vegetables into the baking dish, alternating between squash, potato and parsnip, and fanning them into concentric, overlapping circles. Season generously with salt and pepper and sprinkle a third of the cheese and a third of the chopped herbs over the slices. Repeat twice, making the top layer as neat and tidy as you can.
Remove the garlic clove from the hot milk and pour the milk evenly over the vegetables. Drizzle the remaining olive oil over the top of the gratin and bake for about 50 minutes, until the top is browned and bubbly and the vegetables yield easily when you poke them with a sharp knife. If the vegetables are tender but the top isn’t as brown as you’d like, turn on the broiler for a couple of minutes — watch it carefully so it doesn’t burn! Let the gratin cool for at least 5 minutes before serving.