In a large pot, heat the butter and sauté the tomatoes for 5 minutes. Add the chicken broth and bring to a boil.  Reduce heat to medium and add the vermicelli, salt and pepper to taste, and cook for 10 minutes, stirring occasionally. Remove the pot from the heat and let the soup rest for another 10 minutes.

Serve in bowls garnished with finely chopped parsley and the lemon quarters. If you have any leftover roasted or boiled chicken, cut or shred a cup of the chicken and add it to the soup.