In a bowl mix the flour, butter, a pinch of salt and the water. Work it together to a dough. Place in the fridge for 30 minutes.
Peel and grate the onions, and fry them in a frying pan.
Cut the bacon in thin slices, and add it in the frying pan, and cook on low heat for 5minutes. Let the mixture cool down.
Add the eggs, cream, salt, nutmeg powder and pepper in the frying pan and mix well.
Preheat the oven at 200 degrees Celsius.
Roll out the dough and cover the bottom and the edges of a pie form.
Pour the mixture on the pie dough and sprinkle grated cheese on top.
Place the pie in the oven for 30 minutes and take it out. Serve it warm with a tomato salad.