Write a response to the following query: "What are the main ingredients in a classic Margherita pizza?" Your response should contain at least 3 sentences. Highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. Include keywords *tomato sauce*, *fresh mozzarella*, *basil leaves* in the response. In your response, the word *classic* should appear at least 2 times.

user