Pre-heat broiler
Heat the extra virgin olive oil in a soup pot over medium-high heat. Add the chicken, season with salt and pepper to taste, and cook until lightly browned, 3 to 4 minutes. Add the chopped garlic, the onions, and red pepper flakes, and cook to soften the onions, 5 to 6 minutes. Stir in tomatoes and stock and cook until heated through.
While the soup cooks, char the bread on both sides under the broiler. Rub with garlic haves and drizzle with extra virgin olive oil, then mound with handfuls of parmigiano cheese and return to broiler to melt the cheese, a minute more.
Turn off the heat and stir in the basilll. Pace the arge toasts at the bottom of shallow soup bowls and ladle on the soup, or ladle the soup and float the toast on top to keep them crunchy.