The pissaladière is an onion tart from Nice region, eaten as an appetizer. It is often sold in individual portions by bakery shops and, of course, you can find it at tiny stands on your way to the beach along the Côte d'Azur in the south of France.
Peel and chop the onions and garlic, and cook them in a pan of olive oil for 20 minutes. Stir frequently to keep the onions from browning.
Pre-heat the oven to 450°F.
When the dough is ready, roll it out flat to about 1" to 2" thickness. The dough can then be placed, spread out, into a lightly-oiled pie or tarte pan, or rolled out to a circle (10-12 in. diameter) and put on a flat tin.
(Optionally) Dry the rolled-out dough for 10 minutes in a medium-warm oven. This can prevent to dough from being soggy (if that's a problem).
Spread the onions out evenly on the dough.
Spread about 4 teaspoons of pissala evenly across the dough, and then sprinkle on the olives. Alternately, lay the anchovies and olives out on the dough in a decorative manner, either adding anchovies to the pissala or using in place of the pissala.
Put the pissaladière in the pre-heated oven. After 20 minutes, reduce the oven temperature to and cook for a final 10 minutes.