When you have leftover mashed potatoes and a wedge of blue cheese, you’re a few steps away from a memorable side dish. Think of this as a twice-baked mashed potato or an easy potato casserole that behaves like an elegant potato soufflé. Creamy mashed potatoes gain a tangy lift from gorgonzola or blue cheese, while a crisp herb-breadcrumb topping adds crunchy contrast. It’s a versatile accompaniment that elevates chicken, steak, pork or lamb.
I don’t often have leftover mashed potatoes because, well, mashed potatoes rarely last long. But after holidays like Thanksgiving or Christmas—or when I intentionally make extra—I’ll transform them into this blue-cheese potato soufflé. With a few simple pantry staples, plain mashed potatoes become rich, tangy and just a little bit fancy.
Why you’ll love this recipe:
- Makes use of leftover mashed potatoes.
- Turns simple leftovers into a side dish elegant enough for guests.
- Blue cheese is shown here, but cheddar, gruyère or smoked gouda also work well.
Ingredients:
- Leftover mashed potatoes (about 3 cups)
- 1 egg
- 2 scallions, white and light green parts, chopped
- 1/3 cup milk
- 3 oz blue cheese, crumbled and divided
- 2 slices bread (sourdough or Italian preferred)
- 1/4 cup fresh parsley
- 1 tablespoon butter, cut into small cubes
- Extra blue cheese for topping (about 1 tablespoon)
I use the word “soufflé” loosely—this mixture will puff a bit in the oven, but it’s far from delicate. It’s a hearty, rich bake with bright bites of blue cheese, little bursts of green onion and a silky texture from the mashed potatoes and milk.
Making Twice-Baked Mashed Potato Soufflé
- Preheat oven to 375°F (190°C). Spray a small (3–4 cup) casserole dish with nonstick spray.
- In a large bowl, combine the mashed potatoes, chopped scallions, egg, milk and most of the crumbled blue cheese. Stir until evenly mixed.
- Transfer the potato mixture to the prepared casserole dish and smooth the top with the back of a spoon.
While a traditional soufflé rarely has a breadcrumb topping, this version benefits from a buttery, toasty crumb that contrasts the creamy interior. The topping is quick to make and browns evenly because the breadcrumbs are mixed with butter before baking.
Making the Breadcrumb Topping
- Place the bread slices, parsley and butter in a mini food processor and pulse until you have fine breadcrumbs and the parsley is chopped.
- Sprinkle the breadcrumbs evenly over the potato mixture, then scatter the remaining blue cheese on top.
- Bake 20–25 minutes, until the topping is golden and the dish is bubbly. Serve hot.
I served this left‑over mashed potato soufflé with a pork roast and it was a hit—my family loved the tangy pockets of blue cheese. Although the recipe is listed for six, it disappeared quickly at our table of three. If you prefer a milder flavor, swap the blue cheese for cheddar, gruyère or smoked gouda—each yields a delicious variation.
What to serve with the potato soufflé
- Roast pork or pork loin
- Grilled or roasted beef (flank steak, roast beef)
- Veal chops
- Ham with a brown sugar-mustard glaze
More blue cheese ideas
- Blue cheese pairs well with roasted pears and toasted nuts in salads.
- Toss crumbled blue cheese into warm sweet potato gnocchi or buttery polenta.
- Melt it into a pan sauce for steak or pork for an extra-flavorful finish.
Yukon Blue Potato Souffle
INGREDIENTS:
- 3 cups leftover mashed potatoes (made with Yukon Gold)
- 2 scallions, white and light green parts, chopped
- 1 egg
- 1/3 cup milk
- 3 ounces blue cheese, crumbled, divided
- 2 slices bread (preferably sourdough or Italian)
- 1/4 cup fresh parsley
- 1 tablespoon butter, cut into small cubes
- 1 tablespoon extra blue cheese for topping
DIRECTIONS:
- Preheat the oven to 375°F (190°C). Spray a small (3–4 cup) casserole dish with nonstick spray.
- In a large bowl combine the mashed potatoes, scallions, egg, milk and most of the blue cheese. Stir until well combined and transfer to the casserole dish, smoothing the top.
- Place bread, parsley and butter in a mini food processor and pulse to make fine breadcrumbs and chopped parsley.
- Top the potato mixture with the breadcrumbs and sprinkle with the remaining blue cheese.
- Bake 20–25 minutes until the topping is browned and the casserole is bubbly. Serve hot.
NUTRITION:
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