Caramelized Onion Tart

5 from 1 vote

This tart takes a bit of time, mostly due to the caramelization of onions but you will be rewarded with a sweet, earthy, and rich custard tart with a tender pastry crust.

Course Main Course

Cuisine French

Keyword custard, main, onion, tart, vegetarian

Servings

Calories 377kcal

Author Jenny Ross

Ingredients

Pastry Dough Ingredients:

1 cup almond flour
1/4 cup lupin flour
5 Tablespoons butter softened
2 egg yolks
1/8 teaspoon Salt

Custard Ingredients:

4 T butter
2 large onions halved and sliced thin
3 eggs
3/4 teaspoon Salt
1/2 teaspoon pepper
1 cup heavy cream
Pinch of nutmeg
1/3 cup gruyere finely grated

Instructions

Dough Directions:

Preheat oven to 350 degrees F. Combine flours and salt. Add in yolks and butter and mix until combined. Press into tart pan (It will be just enough to provide a thin). Prick all over with a fork. Line with greased foil (buttered-side down). Fill with pie weights (rice works well) and bake at 350 degress F for 15 minutes. Remove foil and bake another 8-10 minutes, until golden. Remove from oven and cool.

Custard Directions:

While the tart shell is baking, prepare the custard. Heat a large pan over medium high heat. Add butter and when melted, add sliced onions. Cook, stirring often until lightly browned and softened. Reduce the heat and continue cooking until the onions are well caramelized, another 30 minutes.
Whisk together the cream and eggs. Add salt, pepper, and nutmeg. Add the onions and half of the grated cheese. Pour this mixture into the prepared tart shell and top with remaining half of the cheese. Bake until browned and puffy, 25-30 minutes. Cool for 10 minutes before serving.

Nutrition