Heat olive oil in a medium-sized saucepan; add garlic and shallots. Cook 1 minute. Add sausage, cook until browned, about 3 minutes. Add leeks, fennel, carrots, tomatoes, parsley and sprinkle all with salt and pepper. Cook another 2 minutes. Add chicken broth. Cover and simmer over medium heat for about 10 minutes or until vegetables are tender.