How to make
To make the dough, sift the flour with the salt, then add the butter and knead. Add the egg yolk and 1 tbsp (15 ml) cold water. Let it cool for 30 min.
Heat the oven to 390°F (200°C), roll out the dough and put it in a pie form. Press the walls, put baking paper on top and sprinkle on some beans.
Bake the layer for 15 min. Remove the beans and bake another 10 to 15 min. In the meantime, melt the butter and saute the onions for 20 min. Lower the oven to 360°F (180°C).
Sprinkle the layer with mustard and pour on the onions on top. Combine the eggs with the yolk, cream, cheese, nutmeg and salt. Pour it over the onions and bake 30 to 35 min.
