We’ve been sheltering in place for a little while now, so isn’t it time for a bit of a challenge? This savory soufflé recipe, which I originally clipped out of Gourmet magazine nearly two decades ago, is one of my favorite Easter accompaniments for ham. It starts with a simple roux for richness and is lightened with whipped egg whites. Gruyère, a flavorful form of Swiss cheese, is the most challenging ingredient to find, but many grocery stores carry it. Plus, Scardello is currently offering curbside pickup daily at both locations (check here for hours), and they also offer free delivery within a few miles of their stores for orders over $50. (Cheese is an ancient preservation method, so why not stock up your pantry or add a cheese plate and a couple bottles of wine to your order?)
Savory Sweet Potato Soufflé
Since this dish is intended to be served family style, I make it in my mother’s floral 1 1/2-quart soufflé dish. The advantage of a such a dish is that it has higher sides than a normal casserole dish, so the soufflé can rise up against them. But if you have small ramekins, you can use those instead — you’ll just want to shorten the cooking time. Or you can use any large oven-proof casserole dish, you just won’t get as much of that dramatic soufflé rise.
1/2 cup grated Parmesan
1 cup finely diced onion
1 garlic clove, minced
2 tablespoons butter, plus more to grease the soufflé dish
2 tablespoons all-purpose flour
1 cup milk
1 cup grated Gruyère (about 3 ounces)
2 cups mashed cooked sweet potatoes (about 1 1/2 pounds)
4 large eggs, divided
Freshly ground black pepper
Preheat oven to 375 degrees. Butter your chosen pan(s) and dust with 1/4 cup of the Parmesan. This will help the soufflé stick to the sides and rise.
Melt the butter over medium-low heat in a large saucepan. Cook the onion and garlic for a few minutes until softened. Season with salt and pepper to taste. Add the flour and cook the roux, stirring, for 3 minutes (this helps get rid of the raw taste of the flour). Slowly add the milk, whisking constantly, and simmer until thickened. Remove the pan from the heat and stir in the Gruyère, allowing it to melt. Mix in sweet potatoes and then stir in the egg yolks, one at a time. Set the mixture aside to cool.
In a clean, dry bowl, using an electric mixer, beat the egg whites with a pinch of salt until they hold stiff peaks. Start by folding a large spoonful of the egg whites into the sweet potato mixture to lighten it. Then gently fold in the remaining egg whites, using a spatula and a figure-eight motion.
Pour the mixture into the prepared soufflé dish, and sprinkle the remaining Parmesan on top. Bake for 45 to 50 minutes (or less if you are using ramekins), or until it is puffed and golden. Serve immediately.