Name: Rustic Onion Tart
Prep time: 20 min
Cook time: 20 min
Yield: 4
Ingredients: 1 1/4 cup (160 g) all purpose flour -; 1 teaspoon salt -; 5 ounces of butter (1 1/4 sticks, 10 Tbsp, 137g), cubed -; 1/4 cup sour cream -; 3 medium sized red and/or yellow onions (enough for 5 to 8 cups, sliced) -; 2 tablespoons extra virgin olive oil -; 1 tablespoon butter -; Kosher salt -; 1 teaspoon balsamic vinegar -; 3/4 cup (not packed) roughly grated Gruyère Swiss cheese -; 1/2 teaspoon fresh thyme, chopped, or 1/4 teaspoon dried thyme -

Recipe information

Cooking:

20 min.

Servings per container:

Source:

More details

Ingredients for - Rustic Onion Tart

1. 1 1/4 cup (160 g) all purpose flour -

2. 1 teaspoon salt -

3. 5 ounces of butter (1 1/4 sticks, 10 Tbsp, 137g), cubed -

4. 1/4 cup sour cream -

5. 3 medium sized red and/or yellow onions (enough for 5 to 8 cups, sliced) -

6. 2 tablespoons extra virgin olive oil -

7. 1 tablespoon butter -

8. Kosher salt -

9. 1 teaspoon balsamic vinegar -

10. 3/4 cup (not packed) roughly grated Gruyère Swiss cheese -

11. 1/2 teaspoon fresh thyme, chopped, or 1/4 teaspoon dried thyme -

How to cook deliciously - Rustic Onion Tart

1. Stage

Prepare the dough: To prepare the dough, whisk the flour and salt together in a large bowl. Cut the butter into the flour with your hands or with a pastry cutter, until the mixture resembles a coarse meal. Add the sour cream and use a fork to incorporate it into the dough. Gather the dough into a ball and shape it into a disk. Wrap it with plastic wrap and chill for at least an hour.

2. Stage

Prepare the onions: Peel and slice the onions lengthwise from stem to root.

3. Stage

Caramelize the onions: Heat olive oil and butter in a large, heavy-bottomed sauté pan on medium heat. Once the butter has melted, add the onions and sprinkle a little salt over them. Cook, stirring occasionally for 10 minutes, until the onions have softened and are translucent. Reduce the heat to medium low and cook for an additional 40 minutes, stirring occasionally, until the onions are well browned. Add balsamic vinegar and cook for 10 minutes more, until onions are completely caramelized. Remove from heat.

4. Stage

Preheat the oven to 450°F.

5. Stage

Roll out the dough: Remove the dough from the refrigerator and let stand for 5 minutes before rolling it out. Roll out the dough on a lightly floured surface to a 13-inch diameter. Transfer the crust dough to a cookie sheet lined with parchment paper.

6. Stage

Layer the cheese and onions onto the dough: Place all but a couple tablespoons of the cheese in the center of the dough. Spread to within 1 1/2 inches from the edges. Add the caramelized onions, layering them on top of the cheese. Sprinkle with thyme.

7. Stage

Pleat the edges: Fold the edges of the crust dough over so that a small circle of onion is still showing in the centre of the tart. Sprinkle the remaining cheese over the top of the tart.

8. Stage

Bake: Place in the oven on the middle rack. Bake for 10 minutes at 450°F. Reduce the heat to 350°F and bake for an additional 20 to 25 minutes, until the crust is golden brown. Remove from oven and let sit for 10 minutes before serving.