How to make
370°F (190°C) oven;
Baking mold - about 12″ (32 cm)
Butter dough
In a bowl, mix the lemon juice and water. They are set aside.
Mix the flour and salt in the bowl and refrigerate for about 15 minutes to cool.
Grind the frozen butter on the cooled flour (it is good to leave the butter in the freezer before starting for at least about 1 hour). If you don't have time, you can use a fork or a mixer until the flour turns into crumbs. The water is added, but very carefully, as much as it can be squeezed into the palm. It is quickly collected into a ball, wrapped in foil and the butter dough is left in the refrigerator for about 1 hour.
Stuffing
The mushrooms are peeled and they are wiped with moistened kitchen paper. Cut them into slices. It is not necessary to be thin slices. Heat olive oil and 1 tbsp. of butter in a large pan. Add 2 handfuls of mushrooms. This is the quantity, so that you don't overfill the pan, because a large amount of mushrooms they release a lot of water and the frying is very slow.
Leave them on the stove for about 4 minutes, add one part of the pressed garlic, sprinkle with thyme, salt and black pepper. Cook them for another 4 minutes. They are removed with a slotted spoon, a new spoonful of butter is added and a new batch of mushrooms is added. Cook in the same way. The last part of the mushrooms is added. They are removed and placed in a bowl. They are cooled.
In a bowl mix the ricotta and sour cream, yolk and add the mushrooms. Stir very well. The stuffing is ready.
Galette
The cooled dough is placed between two pieces of baking paper or on a floured kitchen counter. Roll it out in a circle (about 30-32 cm). Pour the stuffing into the middle, leaving 1.2″ (3) to 1.6″ (4 cm) from the outer edges without stuffing.
The stuffing is distributed with a spatula. The outer parts of the dough are stuck onto the stuffing. Carefully transfer the galette into the tray. The dough is smeared with a egg white (it is more convenient to roll it out on paper because it is then transferred with the paper directly into the tray).
The delicious savory tart is baked at 370°F (190°C) for about 35-40 minutes.
The mushroom galette is ready.
