Buttered Egg Noodle Potato Casserole

Name: Buttered Egg Noodle Potato Casserole
Prep time: 25 min
Cook time: 45 min
Total time: 1 h 10 min
Yield: 8 servings
Cuisine: American
Ingredients: 2 lb (900 g) russet potatoes, peeled and cut into ½-inch (1.3 cm) cubes; 8 oz (225 g) dried egg noodles; 4 tablespoon (57 g) unsalted butter, divided: 3 tablespoons (43 g) for caramelizing onions, 1 tablespoon (14 g) for sauce; 2 medium (300 g) yellow onions, thinly sliced (about 3 cups / 360 g sliced); 1½ cup (360 ml) sour cream, at room temperature; ¾ cup (180 ml) whole milk, at room temperature; to taste kosher salt; to taste freshly ground black pepper; 3 clove (15 g) garlic cloves, minced; 1 tablespoon (3 g) fresh thyme, leaves stripped from stems (or 1 teaspoon / 1 g dried); 1 cup (115 g) sharp cheddar cheese, shredded; ¾ cup (60 g) panko breadcrumbs; 2 tablespoon (28 g) unsalted butter, melted; ¼ cup (25 g) grated Parmesan cheese (optional)

From the MyKitchenBank Kitchen

A creamy, comforting casserole that combines tender potatoes, buttery egg noodles, caramelized onions, and a sour cream sauce. Golden and rich with a crispy butter-breadcrumb topping, this dish is perfect alongside roasted meats or as a hearty vegetarian main.

Prep: 25 min
Cook: 45 min
Wait: 15 min
Total: 1 hr 25 min
Makes: One 9×13-inch (23×33 cm) casserole, 8 servings

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Ingredients

8 servings

2 lb (900 g) russet potatoes, peeled and cut into ½-inch (1.3 cm) cubes
8 oz (225 g) dried egg noodles
4 tablespoon (57 g) unsalted butter, divided: 3 tablespoons (43 g) for caramelizing onions, 1 tablespoon (14 g) for sauce
2 medium (300 g) yellow onions, thinly sliced (about 3 cups / 360 g sliced)
1½ cup (360 ml) sour cream, at room temperature
¾ cup (180 ml) whole milk, at room temperature
to taste kosher salt
to taste freshly ground black pepper
3 clove (15 g) garlic cloves, minced
1 tablespoon (3 g) fresh thyme, leaves stripped from stems (or 1 teaspoon / 1 g dried)
1 cup (115 g) sharp cheddar cheese, shredded
¾ cup (60 g) panko breadcrumbs
2 tablespoon (28 g) unsalted butter, melted
¼ cup (25 g) grated Parmesan cheese (optional)

Equipment (9)

Large pot (6 quart / 6 L)
9×13-inch (23×33 cm) baking dish
Medium skillet (10 inch / 25 cm)
Large bowl
Medium bowl
Wooden spoon or whisk
Colander
Sharp knife
Measuring cups and spoons

Steps

Before you start

Preheat your oven to 350°F (175°C) and position a rack in the middle.
Have a 9×13-inch (23×33 cm) baking dish ready; you may butter it lightly.
Fill a large pot with salted water and bring to a boil before you start cooking potatoes and noodles.
Bring sour cream and milk to room temperature so they blend smoothly into the sauce.

1
Cook potatoes and noodles
- In a large pot of salted boiling water, add the cubed potatoes and cook for 8 minutes.
- Add the egg noodles and continue cooking for 6–8 minutes more, until the potatoes are just tender and the noodles are al dente (not mushy).
- Drain in a colander and set aside.
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Ready when: Potatoes are tender when pierced with a fork; noodles are soft but still slightly firm
Tip: Do not overcook the potatoes or noodles—they will soften more in the oven. Check for doneness at the shorter times and remove immediately if they are tender.
2
Caramelize the onions
- Meanwhile, in a medium skillet, melt 3 tablespoons (43 g) butter over medium heat.
- Add the sliced onions and cook, stirring often, for 12–15 minutes until they are deeply golden and soft, with browned edges.
- Add the minced garlic and fresh thyme leaves in the last 2 minutes, stirring until fragrant.
- Season lightly with salt and pepper.
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Ready when: Onions are deep golden brown with soft, caramelized edges
Tip: Be patient with caramelization—rushing it on high heat will char the onions instead of sweetening them. Stir frequently to prevent sticking.
3
Make the cream sauce
- In a medium bowl, whisk together the sour cream, whole milk, and remaining 1 tablespoon (14 g) butter until smooth.
- Season generously with salt and freshly ground black pepper to taste.
- The sauce should be creamy and well-seasoned.
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Ready when: Mixture is smooth and homogeneous
Tip: Bringing the sour cream and milk to room temperature beforehand ensures the sauce is smooth without lumps.
4
Combine and assemble casserole
- In a large bowl, combine the cooked potatoes and noodles with the caramelized onions and garlic.
- Pour the cream sauce over and add the shredded sharp cheddar cheese.
- Fold gently with a wooden spoon until everything is evenly coated and the cheese is distributed.
- Transfer the mixture to the buttered 9×13-inch (23×33 cm) baking dish.
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Ready when: All ingredients are evenly combined with sauce coating everything
Tip: Fold gently to keep the potatoes intact and avoid mashing them. Do not overmix, or the texture will become gluey.
5
Prepare the topping
- In a small bowl, combine the panko breadcrumbs, 2 tablespoons (28 g) melted butter, and grated Parmesan cheese (if using).
- Toss with a fork until the breadcrumbs are evenly coated and crumbly.
- Sprinkle evenly over the top of the casserole.
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Ready when: Breadcrumbs are evenly moistened and scattered
Tip: Use melted butter mixed with breadcrumbs for a rich, golden topping. This ensures even browning and prevents dry spots.
6
Bake until goldenOven 350°F / 175°C
- Bake in the preheated 350°F (175°C) oven for 35–45 minutes until the casserole is heated through and the breadcrumb topping is golden brown.
- The edges should be gently bubbling.
- If the topping is browning too quickly, loosely tent with aluminum foil for the final 10–15 minutes.
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Ready when: Topping is deep golden brown; sauce bubbles around the edges; center is heated through (a knife inserted in the center feels hot)
Tip: Watch the topping carefully in the last 10 minutes to prevent over-browning. The casserole may be assembled and refrigerated up to 8 hours before baking; add 10–15 minutes to bake time if baking from cold.
7
Rest and serve
- Remove from the oven and let the casserole rest at room temperature for 10–15 minutes.
- This allows the sauce to set slightly and makes it easier to serve.
- Spoon onto plates and serve hot.
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Tip: Resting is important—serving immediately while the casserole is very hot may result in portions that fall apart on the plate.

Good to know

Tips

For a lighter version, replace half the sour cream with plain Greek yogurt and use low-fat milk. The sauce will be slightly tangier but still creamy and delicious.
Add cooked crispy bacon (4–6 slices, crumbled) or sautéed mushrooms (8 oz / 225 g) to the casserole for extra flavor and texture. Fold them in with the potatoes and noodles.
If using fresh thyme in bunches with tender stems, you can add whole small sprigs instead of stripping leaves—they soften during cooking and add visual appeal.
This casserole pairs beautifully with roasted chicken, prime rib, pork chops, or as a vegetarian main with a crisp green salad and crusty bread.

Make ahead

Assemble the casserole completely, cover tightly with plastic wrap, and refrigerate up to 8 hours before baking. When baking from cold, add 10–15 minutes to the bake time. Do not freeze unbaked casserole, as the noodles may become soft.

Storage & reheating

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in a 325°F (160°C) oven, covered with foil, for 20–25 minutes until warmed through. Do not microwave, as the noodles may become mushy. Freezing is not recommended due to texture changes in the noodles and potatoes.

Substitutions

sharp cheddar cheese, shredded → Gruyère or Swiss cheese. Use the same amount. Gruyère adds a nuttier, more sophisticated flavor; Swiss will be milder and less sharp.
sour cream → Greek yogurt (plain, full-fat). Use 1 cup (240 g) Greek yogurt plus 0.5 cup (120 ml) whole milk to replace the 1.5 cups (360 ml) sour cream. The sauce will be slightly tangier and a bit less rich.
panko breadcrumbs → crushed saltine crackers or crushed Ritz crackers. Use the same amount. Toss with melted butter as directed. The topping will be slightly less crispy and more savory.
fresh thyme → dried dill or Italian seasoning. Use 1 teaspoon (1 g) dried dill or Italian seasoning in place of fresh thyme. Dill adds a bright, herbaceous note; Italian seasoning is more savory.