Quick Recipe Version (TL;DR)
Quick Ingredients
- 3 large yellow onions (about 2 lb/900 g), thinly sliced
- 10 tbsp unsalted butter, divided (3 tbsp onions, 5 tbsp browned, 1 tbsp toss spätzle, 1 tbsp grease dish)
- 1 tbsp neutral oil
- 2 1/2 cups (300 g) all-purpose flour
- 4 large eggs
- 1/2 cup (120 ml) whole milk + 1/4 cup (60 ml) water
- 1 tsp kosher salt (plus 1/2 tsp for onions and 1 tbsp for boiling water)
- 1/4 tsp ground nutmeg; black pepper
- 12 oz (340 g) grated Alpine cheeses: 6 oz Emmental + 6 oz Gruyère
- 1/4 cup (10 g) finely snipped chives
Do This
- 1. Caramelize onions: Cook with 3 tbsp butter, 1 tbsp oil, and 1/2 tsp salt over medium-low, stirring often, 30–40 minutes until deep golden.
- 2. Mix batter: Whisk 300 g flour, 1 tsp salt, 1/4 tsp nutmeg. Beat in 4 eggs, 1/2 cup milk, 1/4 cup water until smooth and elastic, 2–3 minutes. Rest 10 minutes.
- 3. Boil spätzle: Simmer a large pot of water with 1 tbsp salt. Press batter through a spätzle press/colander in batches; cook 1–2 minutes until they float. Drain; toss with 1 tbsp butter.
- 4. Brown butter: In a small pan, cook 5 tbsp butter over medium heat until nutty and amber, 3–4 minutes. Toss with spätzle; season with pepper.
- 5. Assemble: Heat oven to 400°F/200°C. Grease a 2-qt (2 L) baking dish. Layer half the spätzle, half the cheese, a spoon of onions; repeat, reserving a handful of onions for topping.
- 6. Bake 10–12 minutes until melty and bubbling. Broil 1–2 minutes for browned spots. Top with reserved onions and chives; rest 5 minutes and serve.
Why You’ll Love This Recipe
- Classic Alpine comfort: tender, hand-pressed spätzle baked under a blanket of melty Emmental and Gruyère.
- Deep flavor from slow-caramelized onions and nutty browned butter.
- Foolproof technique with options if you don’t own a spätzle press.
- Perfect cozy bake for weeknights or casual entertaining.
Grocery List
- Produce: 3 large yellow onions, fresh chives
- Dairy: Unsalted butter, whole milk, eggs, Emmental, Gruyère
- Pantry: All-purpose flour, neutral oil, kosher salt, black pepper, ground nutmeg
Full Ingredients
Caramelized Onions
- 3 large yellow onions (about 2 lb/900 g), halved and thinly sliced
- 3 tbsp unsalted butter
- 1 tbsp neutral oil
- 1/2 tsp kosher salt
- Optional: 1/2 tsp sugar (helps jump-start caramelization)
Spätzle Batter
- 2 1/2 cups (300 g) all-purpose flour
- 1 tsp kosher salt
- 1/4 tsp ground nutmeg
- 4 large eggs
- 1/2 cup (120 ml) whole milk
- 1/4 cup (60 ml) water
For Cooking & Assembly
- 1 tbsp kosher salt (for the boiling water)
- 1 tbsp unsalted butter (to toss cooked spätzle)
- 5 tbsp unsalted butter (to brown and toss with spätzle)
- 12 oz (340 g) grated Alpine cheeses: 6 oz (170 g) Emmental + 6 oz (170 g) Gruyère
- 1 tbsp unsalted butter (to grease a 2-qt/2 L baking dish)
- Freshly ground black pepper
To Finish
- 1/4 cup (10 g) finely snipped chives
- Reserved caramelized onions (a generous handful)
Step-by-Step Instructions
Step 1: Caramelize the onions low and slow
In a large, heavy skillet over medium heat, melt 3 tbsp butter with 1 tbsp oil. Add the sliced onions, 1/2 tsp salt, and optional sugar. Reduce heat to medium-low and cook, stirring every few minutes, until the onions are deep golden and jammy, 30–40 minutes. If browned bits accumulate, splash in 1–2 tbsp water to deglaze. Set aside; reserve a generous handful for topping after baking.
Step 2: Mix the spätzle batter until stretchy
In a large bowl, whisk flour, 1 tsp salt, and nutmeg. Add eggs, milk, and water. Beat vigorously with a wooden spoon or whisk for 2–3 minutes until smooth, thick, and elastic—the batter should fall in thick ribbons and show long strands when lifted. If too stiff, add 1–2 tbsp water. Rest 10 minutes.
Step 3: Cook the spätzle
Bring a large pot of water to a lively simmer and add 1 tbsp kosher salt. Working in batches, press the batter through a spätzle press or the large holes of a sturdy colander set over the pot, dipping the press/colander in water between batches to prevent sticking. The spätzle are done 1–2 minutes after they float. Scoop out with a spider or slotted spoon, drain well, and transfer to a bowl. Toss with 1 tbsp butter to prevent sticking.
Step 4: Brown the butter and dress the spätzle
In a small saucepan, melt 5 tbsp butter over medium heat. Cook, swirling, until the milk solids turn toasty brown and the butter smells nutty, 3–4 minutes. Immediately pour over the warm spätzle and toss to coat. Season generously with black pepper.
Step 5: Layer with cheese
Heat the oven to 400°F (200°C). Grease a 2-qt (2 L) baking dish with 1 tbsp butter. Spread half the spätzle in the dish. Sprinkle with half the Emmental and half the Gruyère. Spoon over 2–3 tbsp caramelized onions. Repeat with remaining spätzle and cheese, reserving a handful of onions for serving.
Step 6: Bake until bubbling, then briefly broil
Bake 10–12 minutes until the cheese is fully melted and the edges bubble. For browned spots, switch to broil on high for 1–2 minutes, watching closely. Remove and let stand 5 minutes to set.
Step 7: Crown and serve
Top with the reserved caramelized onions and a shower of chives. Finish with a few grinds of black pepper. Serve hot and melty right from the dish.
Pro Tips
- Elastic batter = tender spätzle. Beat until it looks glossy and stretches in long ribbons from the spoon.
- No press? Use a sturdy colander or large-holed grater; push batter through with a bench scraper or spatula.
- Keep the water at a simmer, not a rolling boil, to prevent ragged noodles.
- Shred cheese on the large holes and let it come to room temp for even melting.
- Browned butter goes from perfect to burnt quickly—pull it off the heat as soon as it smells nutty and looks amber.
Variations
- Bacon and Onion: Render 6 oz (170 g) diced bacon or speck until crisp; fold half into the spätzle and sprinkle the rest on top with the onions.
- Mushroom Käsespätzle: Sauté 8 oz (225 g) sliced cremini in butter until browned; layer with the spätzle and cheese.
- Cheese Swap: Try Appenzeller or Raclette for funkier depth, or add 2 oz (55 g) Bergkäse to the mix for extra Alpine bite.
Storage & Make-Ahead
Caramelized onions keep refrigerated up to 5 days. Cooked spätzle can be cooled, tossed lightly with oil, and refrigerated up to 2 days. Assemble the casserole up to 24 hours ahead; cover and refrigerate, then bake 5–10 minutes longer. Leftovers keep 3 days refrigerated; reheat covered at 350°F (175°C) for 15–20 minutes or until hot. You can freeze cooked spätzle (without cheese) up to 2 months; thaw overnight and proceed. Freezing the fully assembled, cheesy bake is not recommended.
Nutrition (per serving)
Approximate: 650 kcal; 38 g fat; 50 g carbohydrates; 27 g protein; 1.8 g fiber; 1,250 mg sodium (varies by salt and cheese).
