Yams and sweet potatoes are sweet. No one can dispute this. There’s a reason they’re just as at home in a pie as they are as a side dish. Even so, a lot of people insist on adding brown sugar, candied nuts, and marshmallows to the orange tubers, because sugar tastes good.
Marshmallows are a bit too cloying for me, however. In the past, I’ve made my own marshmallow fluff to cut down on the sugar and add a little spicy ginger, but I should have just made a Swiss meringue. It’s easier to make and work with than marshmallow fluff, and it browns and crisps in a way that marshmallows simply cannot.
If you’ve never made a Swiss meringue before, it’s just like making any other meringue, with one extra step: Instead of whipping raw egg whites with super fine or powdered sugar, you combine the whites with table sugar, then heat the mixture over a double boiler until the sugar dissolves. (Rub a bit between your fingers. When you can no longer feel any grains of sugar, it’s done.) The resulting meringue is more stable than the uncooked kind, with smaller air bubbles and a more delicate texture.
When spread over a mass of yams or sweet potatoes and broiled, the meringue browns and crisps, creating a thin, crackly layer you’ll have to break through with a spoon in order to access the creamy, buttery orange mash below. (You can make your mash however you want, but I usually cook mine in the Instant Pot, because it is hands-off and delicious.)
Once you’ve got your spuds hot and ready, it’s time to make the meringue. I use this recipe, making sure to whip to stiff peaks. Spread the mixture over the sweet potatoes/yams in a casserole dish, swirling a spoon around to create a fancy pattern. (You could also put it in a piping bag and pipe it out, but I’m never going to do that.) Pop the whole thing in the oven and broil for a minute or two to toast the meringue—really watch it closely—then serve immediately.