Back to the cold, Back to the oven! I find it to be a wonderful ally in the kitchen, because it allows me to not worry about tending to the stove and the result is always fantastic. And this onion cake is good proof of this, you will immediately see why!

This delicious cake has a crispy dough base and a filling of caramelized onions with eggs and milk. In the purest style of a quiche , the cake combines all the ingredients perfectly, resulting in a delicious and versatile dish to enjoy as an appetizer, starter or main course , and that you can serve hot or at room temperature either at home or in a picnic.

The main protagonist of the cake is the onion. It should be cooked over low heat with butter, letting time do its thing and turn it into an ingredient with a completely different flavor and aroma. The onions become soft and sweet, creating a wonderful caramelized flavor . By baking everything together (dough, onion and the rest of the ingredients), the miracle is worked without doing anything else and the result is a dish in which the creamy filling contrasts wonderfully with the crunchy texture of the dough.

Just imagining it makes my mouth water! I leave you the recipe so you can prepare this delight.


For the caramelized onions

  • 500 g onions
  • 50g butter
  • Salt and ground pepper

For the mass

  • 250 g wheat flour
  • 125 g unsalted butter
  • 7 g of salt
  • 7g sugar
  • 10 g egg yolks
  • 30 g whole eggs
  • 60g milk

For the filling

  • 250 g whole milk
  • 250 g whipping cream (whipping cream)
  • 40 g egg yolks (or 2)
  • 180 g whole eggs (or 3)
  • Salt and ground pepper


of the dough

  1. Put the flour and butter in the bowl of your KitchenAid mixer and mix well with the mixing paddle on low speed.
  2. Dissolve the salt and sugar in the milk and add them to the mixture.
  3. Next add the whole egg and egg yolk and mix until integrated and a soft dough is visible.
  4. Roll out the dough between 2 sheets of baking paper until it is 3mm thick. Let the dough rest in the refrigerator for 30 minutes.

From caramelized onions

  1. Peel and finely slice the onions with a knife or a kitchen mandolin .
  2. Sauté the onions with the butter, over low heat and covered, for 20 minutes without browning.
  3. When they are done, let them cool and reserve.

From the filling

  1. Put all the ingredients indicated above for the filling in the glass of the hand mixer (or in a blender).
  2. Add salt and pepper to taste.
  3. Mix until homogeneous, without moving the mixer much to prevent air from entering.

Line the mold

  1. Prepare a removable mold on the counter, or arrange the oven tray perforated with baking film, and a tall round ring in the center. Remove the dough from the refrigerator.
    1. If you want a cake with a rustic and imperfect finish, you can spread the dough as is in a removable mold: simply put it on the base and press the sides so that they remain on the walls of the mold. You can cut the excess dough or fold it inwards.
    2. If you want a homogeneous and more perfect finish (as we have done), place the stretched dough on the perforated tray, and cut two strips about 5 cm wide. With the same round ring, cut the dough into the shape of the disk that will go on the base, 20 cm in diameter.
        • With the ring in the center of the baking tray, put some strips of baking paper on the sides (you can lightly wet the ring to make it adhere).
        • Then, arrange the strips of dough in the ring, pressing to adhere them to the sides of it.
        • Then arrange the dough that you have cut in a circular shape in the center of the ring, in contact with the tray. Press lightly to adhere the ends of the dough to the sides that you have previously placed.

Cake filling

  1. Using a fork, make a few skewers to the base of the cake.
  2. Place the caramelized onions in the center of the dough, in the mold. Distribute to fill the entire interior.
  3. Add the filling mixture that you have previously crushed (the measuring funnel offers you great possibilities).

Step by step onion cake

De Buyer dosing funnel

Baking the cake:

  1. Cook in a preheated oven at 220°C for 20 minutes at a medium/low oven height.
  2. After time, lower the temperature to 170°C and bake for 30 more minutes.
  3. Remove the tray from the oven and place on a cooling rack. When it has lost heat and appears warm, remove the ring (or the removable mold if not available).



  • Onion cake lends itself to endless variations. Don't deprive yourself of adding the ingredients you want to give it different flavors. Play with cheese, fresh aromatics, spices, chopped ham, a little sobrasada or crumbled blood sausage... you decide!
  • You can bake the cake in a round mold with high walls or you can also bake it in a ring by placing a little baking paper on the base.
  • You can also make it in small rings and present individual or portion cakes. In addition to being very cute, you will reduce cooking time in the oven.
  • Serve the cake warm or hot, it's delicious either way! Accompanied by a fresh salad it is a perfect dish.

Onion tart recipe

Recipe author: De Buyer


Claudia&Julia said:

Hola Juana,

Muchas gracias por tu aportación, es muy interesante. En realidad, la receta no lleva 500 g de mantequilla, sino 50 g. Era un error que ya hemos corregido.

Saludos y felices fiestas :)

Claudia&Julia said:

Hola Isi,

Había un error en la cantidad de mantequilla indicada en la receta; son 50 g y no 500 g, por lo que no es necesario escurrirla. En caso de que fueran 500 g realmente lo ideal es escurrirla.

Muchas gracias por tu comentario y felices fiestas :)

¡Un saludo!

Claudia&Julia said:

Hola Carlos María,

Tienes razón, 500 g de mantequilla es una barbaridad. Por suerte, la receta no los lleva; son 50 g. Ha sido un error de transcripción que ya hemos corregido.

Muchas gracias por avisarnos y felices fiestas :)

¡Un saludo!

Juana said:

Yo sustituyo a menudo la mantequilla por aceite, el resultado suele ser excelente si ajustas las cantidades. Por ejemplo ayer hice un bizcocho relleno para cumpleaños y sustituí la mantequilla, normalmente 300 g/ para 300 g harina/ 300 g azúcar por 50 gramos de aceite de oliva virgen, y para suavizar el sabor del aceite añadí una cucharada de extracto de almendras y otra de canela en polvo. Quedó excelente. Si seguimos esta proporción (he probado varias veces) para 500 gramos de mantequilla se podrían usar 85 gramos de aceite. Será cosa de probar.

Isi said:

Las cebollas se escurren cuando se sacan de la mantequilla, al menos yo, lo haría

Carlos María said:

Buenas tardes
La receta tiene una pinta espectacular pero….. ¡500 gramos de mantequilla!!!!! ¿acabaremos en urgencias con las arterias obstruidas?


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