Potato Crusted Onion Tart

Golden, crispy, and irresistibly savory, this Potato Crusted Onion Tart is a show-stopping dish that marries the comforting flavors of a potato rösti and a rich, cheesy quiche. Featuring a potato crust that’s baked to perfection, this tart is filled with luscious caramelized onions, fragrant thyme, and a velvety egg custard studded with Gruyere and Parmesan cheeses. The combination of textures—crispy, creamy, and tender—creates a memorable bite that’s perfect for brunch, a light dinner, or entertaining guests. Simple yet elegant, this recipe highlights pantry staples like russet potatoes, onions, and eggs, while delivering sophisticated flavors. Easy to prepare ahead and served warm or at room temperature, this tart pairs beautifully with a green salad or a glass of white wine for a complete meal.

Nutriscore Rating: 60/100

Prep Time:30 mins

Cook Time:55 mins

Total Time:85 mins

Servings: 8

Ingredients

• 3 medium-sized Russet potatoes
• 3 tablespoons Butter
• 1.5 teaspoons Salt
• 1 teaspoon Black pepper
• 3 large Yellow onions
• 2 tablespoons Olive oil
• 2 teaspoons Fresh thyme leaves
• 3 large Eggs
• 1 cup Heavy cream
• 1 cup Gruyere cheese, shredded
• 0.5 cup Parmesan cheese, grated
• 1 tablespoon All-purpose flour

Directions

Step 1

Preheat your oven to 375°F (190°C). Grease a 9-inch tart pan or pie dish with butter or non-stick cooking spray.

Step 2

Using a box grater or food processor, shred the potatoes. Place the shredded potatoes into a clean kitchen towel and squeeze out as much moisture as possible.

Step 3

In a large bowl, combine the shredded potatoes with 1 tablespoon of melted butter, 1 teaspoon of salt, and 0.5 teaspoon of black pepper. Mix until evenly coated.

Step 4

Press the potato mixture into the prepared tart pan, spreading it evenly across the bottom and up the sides to form a crust.

Step 5

Bake the potato crust in the preheated oven for 25-30 minutes, or until it is golden brown and set. Remove from the oven and set aside.

Step 6

While the crust is baking, thinly slice the onions. In a large skillet, heat the olive oil and 1 tablespoon of butter over medium heat. Add the onions and cook, stirring occasionally, for 20-25 minutes until they are caramelized and golden brown. Stir in the thyme leaves, the remaining 0.5 teaspoon of salt, and the remaining 0.5 teaspoon of black pepper.

Step 7

In a medium bowl, whisk together the eggs, heavy cream, and flour until smooth. Stir in the Gruyere and Parmesan cheeses.

Step 8

Once the potato crust is ready, spread the caramelized onions evenly over the bottom of the crust. Pour the egg and cheese mixture on top, spreading it out evenly.

Step 9

Return the tart to the oven and bake for 25-30 minutes, or until the filling is set and lightly golden on top.

Step 10

Let the tart cool for 5-10 minutes before slicing. Serve warm or at room temperature.

Nutrition Facts

Serving size	(1600.8g)

Amount per serving	% Daily Value*
Calories	2898.1

Total Fat 205.3g	0%
Saturated Fat 104.4g	0%
Polyunsaturated Fat 3.7g
Cholesterol 1056.7mg	0%
Sodium 5622.8mg	0%
Total Carbohydrate 165.4g	0%
Dietary Fiber 17.7g	0%
Total Sugars 26.0g
Protein 88.1g	0%

Vitamin D 153.7IU	0%
Calcium 1800.6mg	0%
Iron 11.2mg	0%
Potassium 3903.3mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 64.6%

Protein: 12.3%

Carbs: 23.1%