Upside-Down Tart with Red Onion

This onion tart has become popular at my home and also quite appreciated when I serve it to my guests so I would like to save this recipe here. The tart is so nice thanks to that perfect dough it is made with. It is flaky as puff pastry but ;not so dry. It is also slightly short and sandy. Because the dough is baked on top of the tart it is not get the moisture from the layer of vegetables and remains crunchy once baked.

This particular tart with red onion is a kind of cold weather dish, but it can be made with a different vegetable depending on season turning it into a spring or summer version. It also can be made with fruits as a dessert. There are no eggs or cream added to the filling just a little bit of goat cheese, and an apple which adds the extra sourness to the tart.

Upside-Down Red Onion Tart

Ingredients:

For the dough--for a 10-inch shallow baking form:
1 cup all purpose flour,
1 stick (8 tbsp) cols unsalted butter, cut into thin slices
4 tbsp iced water,
1 tsp salt,

For the onion layer:
2–3 red onions peeled and sliced in a medium thick slices,
1 cooking apple, preferably sour, peeled, cored and cut into thin wedges,
1/2 cup crumbled goat cheese,
1 tsp fresh or dried thyme,
salt and pepper to taste,
olive oil for frying.

Preparation:
1. Sift flour onto a working surface. Add salt and butter. Coat the butter with flower. Using fingers smash butter with flower until you get pieces similar to cornflakes, with as much flour as possible incorporated in the butter.
2. Sprinkle cold water on top of the mixture and start to make a ball scraping the dough using a scraper or a wide blade knife. Make a ball by scraping, pressing and folding the dough until almost a smooth ball forms. It can still have some visible pieces of butter in it.
3. Finally, roll out the dough between 2 sheets of plastic foil to an inch thick layer, fold in three and put in a refrigerator for 30 minutes.
4. Remove the dough from the refrigerator. Roll it out again with a rolling pin to an inch thick disk and fold in three again. Repeat two times. When the dough is folded for the third time wrap it in a plastic foil and chill for 20 minutes in a refrigerator.
5. To prepare the filling, heat 2 tbsp of olive oil in a frying pan. Add onion slices and fry until slightly brown. You can try to preserve the whole slices for a nice presentation, or just mix them.

6. Transfer the fried onion from the frying pan to the bottom of the baking form coated with oil. On the same frying pan heat one tbsp of olive oil and fry apples until soft. Spread them on top of the onion. Season with salt and pepper and finish with thyme.

7. Preheat oven to 375F.
8. Roll out the dough to a 10-inch circle. Transfer it on a rolling pen to the baking form so it covers the onion.

9. Pierce the dough a few times with a fork and bake for about 40 minutes until the top is dark gold.
9. Cool the tart slightly, cover with large serving plate and flip over on the plate. Cut and serve.