Mellowed marshmallows: A divisive side dish finds redemption

By Eric Kim

The New York Times

In the brackish marshes of the American Northeast grows Althaea officinalis, the marsh mallow plant, whose tough, tan-white roots can be boiled and used in place of egg whites in a meringue, or gelatin in homemade marshmallows.

The ancient Egyptians once harnessed the plant’s thickening powers, mixing its sap with honey and nuts for a confection considered a candy for the gods. Later, in the 19th century, when European confectioners replaced the sap with gelatin and figured out how to mass produce it, the marshmallow came down to earth.

And lucky for us.

Now, every year on Thanksgiving, the grocery-store shelves are rife with marshmallows, ready to top many a sweet potato casserole. For some, that plush-topped Thanksgiving staple is a yearly burst of saccharine sunshine. For others, it’s a repulsion of gastronomic proportions. Why top an already sweet dish with sugary candy? To understand, it might help to look at the recipe’s creation.

In 1917, the Angelus Marshmallow company hired Janet McKenzie Hill, a prolific cookbook author, food scientist and the founder of The Boston Cooking School Magazine, to create recipes that used its marshmallows. One of those inventions was the casserole we know today: mashed DayGlo-orange sweet potatoes topped with bloomed and burnished snowy marshmallows.

This year, I wanted to create a decidedly savory version that made a case for marshmallows’ rightful place on top of the casserole — and alongside the turkey, stuffing, green bean casserole and macaroni and cheese. My reasoning was not just because the original called for them, but because there’s something satisfying about a root-vegetable dish topped with a candy with origins in nature.

Here are my must-do recommendations for a dish that’s sweet, but not too sweet:

1. Bake — don’t steam — your sweet potatoes

The Idaho Potato Commission recommends not wrapping your spuds in foil, since trapped steam can cause sogginess. Instead, bake them whole, naked on a sheet pan, to reduce their moisture, and look for caramelly bubbling — that’s how you know your sweet potatoes are truly cooking. Cooking them this way results in a fluffier mash and concentrates their naturally honeyed flavor. Your final casserole will taste even more sweet potatoey.

2. Anchor the sweet with some savory

Borrowing a little flavoring trick from chef Nick Anderer of Anton’s and Leon’s in New York, I add woodsy bay leaves and fruity black pepper, steeped in heavy cream, which give the sweet potatoes an undeniable savoriness. You could use sage or thyme or rosemary, as well, but there’s nothing like the combination of mentholly bay leaf and sugar-white marshmallows.

3. Halve the marshmallows vertically

In this recipe, the marshmallows are a necessary ingredient rather than a quirk: Halved vertically and toasted under the broiler, they create a thin, bittersweet shell that crackles and complements the potatoes, providing most of the dish’s sweetness.

4. Finally, consider a nut, any nut

The sweet potato casserole might be associated with the American South, but Hill, its creator, was based in the North. When the root-on-root delicacy arrived in the South (most likely via her recipe booklets), the too-sweet marshmallows were swapped out for nuts, often in some form of streusel or praline. A handful of pecans, which are native to North America, scattered atop the marshmallows lends necessary richness and crunch.

Marshmallow-Pecan Sweet Potato Casserole

At last, here is a version of this Thanksgiving casserole that’s not too sweet, thanks to a few smart, simple tricks. First, the potatoes are baked whole to concentrate their flavor and reduce their moisture for a fluffy mash. Woodsy bay leaves and fruity black pepper perfume the potatoes with undeniable savoriness. There are no extra spices here, just plenty of salt, so the natural earthy sweetness of the spuds can shine. The marshmallows are necessary, not a retro quirk: Halved and toasted under the broiler, they create a crackly thin, turtle-shelled top that complements the potatoes and provides most of the dish’s sweetness.

Makes 8 to 10 servings

INGREDIENTS

4 large sweet potatoes, scrubbed (about 2 1/2 pounds)

1/2 cup heavy cream

3 bay leaves, preferably fresh

1 teaspoon freshly ground black pepper, plus more to taste

3 tablespoons unsalted butter, at room temperature, plus more for greasing pan

1 to 2 tablespoons dark brown sugar

1 teaspoon coarse kosher salt, plus more to taste

2 large eggs, at room temperature

20 large marshmallows, cut in half lengthwise (about 5 ounces)

1/2 cup roasted salted pecans (see Tip)

DIRECTIONS

1: Arrange a rack 6 inches from the broiler heat source and another rack in the center of the oven. Heat the oven to 425 degrees.

2: Line a sheet pan with parchment paper or foil. Prick the sweet potatoes all over with a fork and place on the pan. Bake on the center rack until the potatoes are fork-tender, 1 to 1 1/2 hours.

3: Meanwhile, in a small saucepan, heat the heavy cream, bay leaves and black pepper until bubbling at the edges and steaming. Remove from the heat and let steep until the cream is fragrant and the potatoes are cool enough to handle.

4: Using your fingers, peel the potatoes (the skins should slip right off), then add the flesh to a large bowl. Pour the cream over the potatoes, holding back the bay leaves and discarding them, then add the butter, brown sugar and salt. Whisk until smooth. Taste and add more salt and pepper if desired (the potatoes should taste deeply savory, like mashed potatoes). Set aside to cool slightly.

5: Reduce the oven temperature to 350 degrees. Grease a 2-quart shallow casserole dish with butter. Whisk the eggs into the potatoes until fluffy, about a minute. Spread the mixture in the dish, then place the marshmallow halves, cut sides down, in a single layer across the top, leaving small slivers of space between them (they’ll expand as they bake). Sprinkle with the pecans. (You can cover and refrigerate the casserole at this point for up to 2 days, until ready to bake.)

6: Bake until lightly browned on top and hot through the center, 20 to 25 minutes. (If the casserole was refrigerated, it may take longer to heat through.) Take the casserole out of the oven and heat the broiler.

7: Place the dish under the broiler until you see a wisp of smoke and the marshmallows are deeply and evenly browned, 1 to 2 minutes. Do not take your eyes off the dish, as the marshmallows can burn in an instant. Serve hot or warm.

Tips:

If you can’t find roasted salted pecans at the store, toast raw ones in a 350-degree oven until fragrant, 8 to 10 minutes, and toss with a drizzle of oil and a sprinkle of salt to lightly coat. Cool completely before using.

Recipe by Eric Kim.