Take the dough out of the fridge about 10 minutes before preparation. Clean and wash the spinach. Peel onion and garlic, dice finely. Wash and halve the tomatoes.
Heat the oil in a pan. Sauté the onion and garlic in it. Add the dripping wet spinach and let it collapse. Season with salt and pepper. Add the tomatoes and fry briefly.
Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: level 4). Whisk eggs and milk. Season with salt and pepper. Roll out the puff pastry on the paper and cut into 4 squares.
Rinse four ovenproof moulds (each approx. 11 cm Ø) in cold water. Put 1 disc of dough in each, press on the rim. Spread the spinach with the tomatoes on top. Pour the egg milk over them. Sprinkle with pine nuts and bake in a hot oven for 20-25 minutes.