A Classic Cheese and Onion Flan

Cheese and Onion Flan Recipe

 The Spruce

  • Total: 70 mins
  • Prep: 20 mins
  • Cook: 50 mins
  • Chill: 30 mins
  • Servings: 6 servings
Nutritional Guidelines (per serving)
782 Calories
59g Fat
48g Carbs
16g Protein
See Full Nutritional Guidelines Hide Full Nutritional Guidelines
Nutrition Facts
Servings: 6
Amount per serving
Calories 782
% Daily Value*
Total Fat 59g 76%
Saturated Fat 23g 115%
Cholesterol 206mg 69%
Sodium 850mg 37%
Total Carbohydrate 48g 17%
Dietary Fiber 4g 13%
Protein 16g
Calcium 251mg 19%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

Do not confuse a classic cheese and onion flan with a quiche. While this baked egg recipe may resemble the traditional French dish, the flan is made differently and tastes a little different. It is the traditional British version of the ubiquitous quiche and, for many Brits, is the stuff of memories. Those memories being school lunches, summer meals, afternoon tea, and dinners with the flan served alongside a salad and often boiled new potatoes.


  • For the Pastry:
  • 200 grams plain flour (or all-purpose flour)
  • 110 grams butter (or an equal mix of butter and lard; cubed)
  • 1 pinch salt
  • 2 to 3 tablespoons water (very cold)
  • For the Filling:
  • 55 grams butter
  • 2 tablespoons extra-virgin olive oil (or sunflower oil)
  • 1 large yellow onion (peeled, finely sliced, and sautéed)
  • 3 to 4 large eggs (200 ml)
  • 75 grams mature cheddar cheese (coarsely grated)
  • 2 to 3 tablespoons flat-leaf parsley (chopped)
  • 1 cup milk
  • Salt (to taste)
  • Freshly ground black pepper (to taste)

Steps to Make It

  1. Gather the ingredients.

    Cheese and Onion Flan crust ingredients
     The Spruce
  2. Place the flour, butter (or butter and lard mix), and salt into a large, roomy mixing bowl. Rub the butter into the flour until it resembles sand.

    Butter and flour mixed in a bowl
     The Spruce
  3. Add the water a little at a time and bring the mixture together to create a soft dough.

    Flan dough in a bowl
     The Spruce
  4. Leave the pastry to rest wrapped in clingfilm in the refrigerator for 30 minutes.

    Dough wrapped in plastic wrap
     The Spruce
  5. While the pastry is resting, prepare the filling.

    Cheese and Onion Flan filling ingredients
     The Spruce
  6. Heat the butter and oil in a saucepan. Once melted, add the sliced onion and cook over medium heat to soften (but not brown) the onions. Place the softened onions onto a dinner plate and leave to cool. 

    Onions cooking in a pot on the stove
     The Spruce
  7. Preheat the oven to 400 F/204 C. Roll the pastry to 5 millimeters thickness and line a greased, 10-inch loose-bottomed tart tin. Chill in the refrigerator while you make the remaining filling. 

    Lined tart tin with pastry
     The Spruce
  8. Put the eggs into a large measuring jug and whisk them. Add the cooled onions, grated cheese, parsley. Top up with the milk. Season with a little salt and black pepper. 

    Cheese and Onion Flan filling in a measuring cop
     The Spruce
  9. Take the pastry case from the refrigerator, place it on the middle shelf of the preheated oven, and carefully pour in the egg-cheese mixture until it is two-thirds full. Do not overfill as the flan will rise while cooking.

    Cheese and Onion Flan in the oven
     The Spruce
  10. Bake for 30 to 40 minutes until the top is golden brown and set, but not completely solid when gently pressed in the center.

    Cheese and Onion Flan cooling on a cutting board
     The Spruce
  11. Remove from the oven and rest for 5 minutes before serving.

    Cheese and Onion Flan cooling on a rack
     The Spruce
  12. The flan is lovely warm, but can also be eaten cold. 

    Cheese and Onion Flan Recipe
     The Spruce
  13. Enjoy!

Recipe Variations

  • Add bacon pieces or tiny cubes into the egg for the meat-eaters. 
  • Use a different cheese; crumbly blue is amazing. 
  • Change or add a different herb. The softer ones such as basil, tarragon will work best.

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