Pizza is a dish of Italian origin consisting of a usually round, flat
base of leavened wheat-based dough topped with tomatoes, cheese, and
often various other ingredients (such as various types of sausage,
anchovies, mushrooms, onions, olives, vegetables, meat, ham, etc.),
which is then baked at a high temperature, traditionally in a wood-fired
oven. A small pizza is sometimes called a pizzetta. A person who makes
pizza is known as a pizzaiolo.
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