Ingredients:
- 1 lb (450g) yellow onions, thinly sliced
- 3 tbsp (42g) unsalted butter
- 1 tbsp (15ml) olive oil
- 1/2 tsp (3g) kosher salt
- 1/4 tsp (1g) black pepper
- 2 cups (250g) all-purpose flour
- 3 large eggs, room temperature
- 1/2 cup (120ml) sparkling mineral water
- 1/2 tsp (3g) kosher salt
- 1/4 tsp (1g) ground nutmeg
- 2 cups (225g) Gruyère cheese, shredded
- 1 cup (115g) Emmental or Swiss cheese, shredded
- 2 tbsp (28g) unsalted butter
- Fresh chives, chopped
Instructions:
- Heat the olive oil and 3 tbsp of butter in the skillet over medium-low heat.
- Add the sliced onions and salt. Cook, stirring occasionally, for 20-30 minutes until the onions are a deep mahogany brown and smell intensely sweet and nutty. Remove from heat and set aside.
- In a large bowl, whisk together the flour, salt, and nutmeg.
- Create a well in the center and add the eggs and sparkling water.
- Beat the batter vigorously with a whisk or hand mixer for 3-5 minutes until the batter is thick, glossy, and makes a slapping sound when lifted.
- Bring a large pot of salted water to a boil. Using a spaetzle press or grater, push the dough into the boiling water. Cook until the noodles float to the surface, then remove with a slotted spoon.
- In the skillet with the caramelized onions, melt the remaining 2 tbsp of butter. Add the cooked spaetzle, Gruyère, and Emmental cheese. Stir over low heat until the cheese is melted and creamy.
- Season with black pepper and garnish with chopped fresh chives before serving.