This thick meal brims with vegetables. The tang comes from a spoonful of vinegar that is tossed with toasted bread and added to the soup at the end of cooking."
Advance preparation: You can make this through step 4 up to a day ahead of serving. You might want to hold off adding the chard until you reheat if you want it to have a nice color. Bring the soup to a simmer, add the chard and simmer 10 minutes, then proceed with step 5.

You can finish this hearty summer soup with slivered fresh basil or with pistou, the Provençal version of pesto. (It’s pesto without the pine nuts.) A Parmesan rind, simmered in the soup and then removed, provides great depth of flavor without additional fat. On a hot summer day in Italy, the soup might be served at room temperature or just barely warm.
Advance preparation: The soup can be made through step 2 a day or two ahead. It improves overnight. If you’re making the soup ahead, cook the pasta separately and add to the soup, along with the green beans on the day you are serving it.