Preheat oven to temperature indicated on dough package or recipe.
Heat the oil in a large skillet over medium heat. Add the onion, fennel and a pinch of salt; cook, stirring often, 10-15 minutes, or until lightly browned. Reduce heat to low and cover; cook 5 minutes more or until softened. Uncover and stir in water; continue to stir until the mixture is golden brown. Stir in Italian seasoning and add more salt to taste if needed. Remove from heat.
While the onion and fennel are cooking, roll out the pizza dough according to package instructions and transfer to a parchment-lined baking sheet or pizza stone.
Spread the onion and fennel mixture over the crust. Top with the mozzarella cheese and scatter olives over the cheese.
Bake for 15-20 minutes (or time indicated on dough package), or until the cheese is melted and the dough is golden. Remove from oven, sprinkle with grated parmesan (if using), and slice into 6 pieces.