The name, 're-boiled', suggest it was originally any soup made of leftovers. Now it's a classic of Tuscan cucina povera. Ribollita needs three things: bread, white canellini beans, and vegetables; popular ones include carrot, cavolo nero and onions. 'Re-boiled' also refers to the fact that usually cooks make enough to heat it up the next day, when the flavours have mingled and it tastes better.
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