Tips & Tricks
We used a single sheet of pie dough. We cut it in half and covered the first half with the filling. We then covered the pie with the other half. We press the edges with the tines of a fork to make sure it is tightly sealed all around. You can use two whole sheets if you prefer.
You can beat an egg and brush a little over the pie to glaze when baking.
If you have large tomatoes, one will be enough. If your onion is very large, just use half.
You can easily find ready-made pie dough. Puff pastry will also work well.