The perfect dish for the cooler weather of fall, we love making this authentic German onion pie, also called Zwiebelkuchen.
We love eating this German onion pie. Growing up in Southern Germany, my oldest memories involving Zwiebelkuchen are my mom actually buying (not making!) warm onion pie. Maybe I wasn’t so fond of it then …
However, these days we can’t get enough of it. Being somewhat similar to a Quiche Lorraine or “Flammkuchen” (tarte flambée), it is one of those typical traditional German dishes that you can find everywhere in Germany in the fall.
The cultural background of Zwiebelkuchen
Of course, you can eat German onion pie any time of year you want. For me, it only tastes right in the fall. By fall, I also mean the grape harvest season. This is when you would traditionally see it being made and served in Germany.
You see, when the vintners and wineries had harvested their grapes and began making wine, they will also let you buy and try their just fermenting wine. Depending on its age, it will be somewhere between grape juice and fully fermented wine. With each day, it will lose some of its sweetness and become more alcoholic. Germans call this not fully-fermented wine “neuer Wein” (new wine), “Federweisser” (literally meaning feather white), or “weißer Sauser” (you can read more about it here).
Most of these wineries aren’t set up as restaurants but in the fall, they might serve their young wine – and Zwiebelkuchen. To let people know that they are doing so, they will have a broom by their front door. Thus, they are called “Besenwirtschaft” (something like a broom pub). That is why onion pie and very young wine go so well together.
For some reason, you cannot buy this still fermenting wine in this country so I make my own. Just to have it with my Zwiebelkuchen.
How to serve German onion pie
Knowing the cultural background of German onion pie gives you a hint of how to serve it and eat it.
Ideally, you eat it warm not hot straight from the oven. Trust me, it will taste better that way! Even though I think it’s perfect with this young wine called Federweisser, you can drink anything you like with it. If you enjoy wine but can’t get this still-fermenting wine, you could serve either a Riesling-style wine with it or a rose wine.
To make this a meal, I suggest making a green salad of butter lettuce with a mild dressing. This would also be the traditional way you would find this in Germany.
Ingredients for German onion pie
These are the traditional ingredients:
- onions: I recommend regular white onions, not sweet onions. As they are the main ingredient here, make sure to buy high-quality onions
- eggs: these will help the pie to set. I always recommend you use the best ingredients you can afford. Therefore, we love using organic pasture-raised eggs
- bacon: bacon adds a bit of a bite and a nice saltiness to the onion pie. We love bacon from pasture-raised pigs but any bacon will work here
- sour cream: the addition of sour cream counters the sweetness of the onions and gives it a more complex taste
- Dijon mustard: while not being entirely traditional, I love adding a teaspoon of Dijon mustard. It adds just enough of a kick to this dish that I really miss in recipes that don’t use mustard
- caraway seeds: I really like to add them since they help you digest the onions. Most people don’t even notice them all that much
- AP flour: I like to add some flour to sop up any onion juices
- salt & pepper: I don’t think I need to say anything here
- a crust: depending on the type of dish you are using, you can use a pastry crust or yeast dough. Either one would be fine. I actually like to use a sourdough pizza crust and will link it here once I am happy with my recipe.
Simple pizza crust
You may have your favorite pie crust or pizza dough recipe but if you don’t here’s a very simple one:
- 1 tsp active dry yeast
- 1 cup warm water (110 degrees F/45 degrees C)
- 2 ½ cups bread flour
- 2 tablespoons olive oil
- 1 teaspoon salt
Mix all the ingredients together and knead for 5 minutes. Place the dough in a lightly greased bowl, cover, and let rise for at least one hour. You can also place it in the refrigerator overnight and use it the next day.
How to make the German onion pie
- Dice 4-5 slices of bacon coarsely. If you want to taste the bacon you can make the pieces bigger, if you don’t want it to stand out, chop it into smaller pieces
- Peel and finely slice 2 ¼ pounds of onions. I like to slice them as thinly as I can. That way they will cook faster and won’t be so “chewy” in the finished dish. I do this by hand but you could use a mandolin or food processor.
- Sautee the bacon in a skillet. I use my cast-iron skillet and prefer browning the bacon a bit to make it crisp.
- Add the onions. You can add them gradually or all at once. Make sure to stir them a bit to break up any slices that might be stuck together.
- Cook the onions. I like to put a lid on and cook the onions over low heat until very soft and translucent. Make sure not to brown (caramelize) them. Let them slightly cool down.
- To a medium bowl, add 4-5 eggs, 1 ½ cups of sour cream, 1 teaspoon of Dijon mustard, 1 teaspoon of salt, 1 teaspoon of caraway seeds, and some fresh ground pepper. Whisk until well-combined
- Add the onions and bacon to this mixture and stir well.
- Preheat the oven to 375˚ F.
- Press the pie crust or pizza dough into a greased rectangular baking dish (I am using a 12″x17″ stainless steel baking pan).
- Add the onion-sourcream mixture and spread evenly.
- Bake at 375˚F for 40-55 minutes or until the onion pie is set and golden brown. Serve warm.
Authentic German Onion Pie (Zwiebelkuchen)
- 2 ¼ pounds onions
- 4-5 slices bacon
- 4-5 whole eggs
- 1 ½ cups sour cream
- 1 TBSP AP flour
- 1 tsp Dijon mustard
- 1 tsp caraway seeds
- 1 tsp salt
- fresh ground pepper
- 1 whole pie crust or pizza dough (see notes)
- Coarsly dice the bacon slices. Set aside.
- Peel and finely slice the onions.
- Preheat a large heavy skillet and saute the bacon until crisp.
- Gradually, add all of the sliced onions. Stir well. Cook covered until the onions are translucent and soft but not brown. When finished, let them cool doen slightly.
- To a medium bowl, add the eggs, sour cream, mustard, flour, caraway seeds, salt, and some fresh ground pepper. Mix well until combined.
- Add the onions to this egg-sour cream mixture.
- Press the crust or pizza dough into a lightly greased, rectangular baking dish.
- Preheat the oven to 375˚F.
- Pour the onion mixture over the crust and spread out evenly.
- Bake at 375˚F for 40-55 mins or until set and golden-brown.
- Serve warm.
Can you substitute or add ingredients to the German onion pie?
There are so many different variations of this German onion pie out there.
Since people tend to either love or hate caraway seeds, you can omit them if you are in the latter group.
I have seen recipes in which you add some grated Gruyere cheese on top. While this sounds delicious, it is not the most traditional way to make Zwiebelkuchen.
There are also recipes out there that use sweet cream instead of sour cream. I prefer the latter but if you don’t have or like sour cream, you can absolutely make this recipe with heavy cream.
There is a certain look to this German onion pie with the onions cut into thin slices. However, I have seen recipes that use diced onions, instead. In the end, I think this is mostly a matter of personal preference.
What crust you choose, really depends on what you like. I have made both a pie crust and a pizza dough. Lately, I have been experimenting with a sourdough crust but need to tweak it more before I feel like I can share it. Some recipes recommend a phyllo dough crust. And interestingly enough, I have seen recipes in which you make the German onion pie with no crust at all!
As for the type and shape of the baking dish, you can use whatever you have. In this recipe, I used a 12″x17″ stainless steel baking dish that resulted in a flat tart. You can absolutely use a smaller baking dish that will make the onion pie higher. In the past, I have also used a round springform pan.
So you see, there are so many possibilities!