Zwiebelsauce (German Onion Sauce) is a naturally dairy-free, savory sauce that’s perfect for serving over Spätzle or alongside other German dishes. This classic recipe uses caramelized onions, broth, and a touch of vinegar for deep, comforting flavor—no cream required! If you’re looking for a traditional German sauce that’s both rich and plant-based, this is a must-try.
Ingredients
- 3 large yellow onions, thinly sliced
- 2 tablespoons vegetable oil or vegan butter
- 1 tablespoon all-purpose flour
- 1 cup vegetable broth (or beef broth for a non-vegan version)
- 1/2 cup dry white wine (optional, or use more broth)
- 1 teaspoon sugar
- 1 tablespoon apple cider vinegar or white wine vinegar
- 1/2 teaspoon salt (or to taste)
- 1/4 teaspoon black pepper
- 1/2 teaspoon dried thyme (or 1 teaspoon fresh)
- 1 bay leaf
- Chopped fresh parsley (optional, for garnish)
Instructions
- Caramelize the Onions:
Heat the oil in a large skillet over medium heat. Add the sliced onions and sugar. Cook, stirring often, until the onions are golden brown and caramelized, about 20–25 minutes. Don’t rush this step—the flavor develops as the onions slowly brown. - Add Flour:
Sprinkle the flour over the onions and stir well. Cook for 1–2 minutes to remove the raw flour taste. - Deglaze and Simmer:
Add the white wine (if using) and scrape up any browned bits from the bottom of the pan. Let it simmer for 2–3 minutes until slightly reduced. Add the broth, vinegar, thyme, bay leaf, salt, and pepper. Stir to combine. - Simmer the Sauce:
Reduce heat to low and let the sauce simmer gently for 10–15 minutes, stirring occasionally, until thickened and flavorful. Remove the bay leaf. - Finish and Serve:
Taste and adjust seasoning as needed. Serve hot over Spätzle, and garnish with chopped parsley if desired.
Tips & FAQ
- Can I make this ahead? Yes! Zwiebelsauce reheats well. Store in the fridge for up to 3 days.
- What if I don’t have wine? Just use extra broth instead.
- Is this sauce gluten-free? Use a gluten-free flour blend to thicken if needed.
- What else can I serve this with? Try it over mashed potatoes, roasted vegetables, or vegan schnitzel.
Looking for more German recipes? Check out our German recipe collection!
