Potato, Potahto

This year for Thanksgiving, I was assigned to make a mushroom and potato gratin. I love trying new things and this sounds particularly delicious. But. What about the gravy? Gravy doesn't go on gratin and you can't really have turkey without making gravy. It definitely presents a problem. One that can be easily solved: Make the gratin and ALSO a big pot of mashed potatoes.

It's total excess - there will only be about 15 of us - but there's something to be said for planning Thanksgiving with the expectation of leftovers.

I am having a Thanksgiving Leftover Brunch next Saturday to see who can make the best dish with turkey-day leftovers. I haven't decided what I'm making yet, but I think I should probably do something with the massive potato leftovers we will have.

What would you bring to my brunch?

Here's the recipe for the gratin:




Potato and Mushroom Gratin
from Bon Appetit, December 2008


5 tablespoons olive oil, divided
2 1/2 pounds medium Yukon Gold potatoes, peeled, cut lengthwise into 1/8-inch-thick slices
1 1/2 teaspoons coarse kosher salt plus additional for mushrooms
3/4 teaspoon freshly ground black pepper plus additional for mushrooms
1 1/4 cups (or more) heavy whipping cream, divided
1 cup freshly grated Parmesan cheese (about 3 ounces), divided
2 tablespoons chopped fresh thyme
6 garlic cloves, thinly sliced
12 ounces fresh crimini (baby bella) mushrooms, sliced

Preheat oven to 375°F. Brush 13x9x2-inch glass or oval ceramic baking dish with 2 tablespoons oil. Arrange 1/3 of potatoes, slightly overlapping, in dish. Sprinkle with 1/2 teaspoon coarse salt and 1/4 teaspoon pepper. Pour 1/3 cup cream over; sprinkle with 1/4 cup cheese. Repeat layering 1/3 of potatoes, 1/2 teaspoon salt, 1/4 teaspoon pepper, 1/3 cup cream, and 1/4 cup cheese 2 more times. Bake uncovered until potatoes are tender, adding cream by tablespoonfuls if dry, about 45 minutes. Remove from oven; maintain oven temperature.

Sprinkle thyme and garlic slices over gratin. Toss mushrooms in medium bowl with 3 tablespoons oil; sprinkle with coarse salt and pepper. Arrange mushroom slices atop gratin around edge of dish. Drizzle with 1/4 cup cream; sprinkle with 1/4 cup cheese. Continue to bake uncovered until mushrooms are tender and potato edges are golden brown, about 20 minutes longer. DO AHEAD: Can be made 1 day ahead. Cool 1 hour in dish; cover and chill. Before serving, cut gratin into 10 pieces. Transfer to rimmed baking sheet. Cover with foil and rewarm in 350°F oven, 10 to 15 minutes.