Fit the pie crust to a tart pan, using a rolling pin to cut off the top edges. Place in freezer for 15 minutes or longer, then bake at 400°F for 10 minutes. Remove from oven and let cool before filling.
Meanwhile, melt the butter in a pan and add onions cooking about 5 minutes. Add zucchini and cook 10 minutes longer. Salt and pepper to taste. Remove from heat and spread evenly into bottom of cooled pie crust.
Sprinkle evenly with goat cheese. Beat the eggs with the crème fraîche, nutmeg and salt and pepper. Pour on top of vegetables and cheese and bake for 30 minutes at 400°F.
Serves 6