For the dough: sift the flour and gently incorporate the very cold butter, cut into cubes, using your fingertips.
Add the eggs, milk, sugar, and salt, and shape the dough.
Transfer the dough into a 23 cm diameter tart pan, spreading it evenly over the entire surface and trimming any excess dough as needed.
Chill the pan for 40 minutes,
then remove it, prick it in spots with a fork, and bake for 15 minutes at 170 °C.
For the filling:
In a pan, add the butter with the oil and the washed spinach well drained of water, mix until softened.
In a bowl, mix together: sour cream with eggs and cheese, season with salt and pepper to taste. Add the soaked spinach and cubed fish, mix.
Add over the dough, sprinkle with previously roasted pine nuts, and bake for another 20 minutes.
Serve the tart hot or cold with herbs.
Happy holidays!
