Many kinds of canned beans will work well in this recipe, which also combines zucchini and fresh green beans with sliced fennel and Parma ham. Try a combination of small and large canned beans of different colours.
Recipes that use fennel sometimes list celery as an alternative. Although they are similar in texture, the nutritional differences between the two are significant. Fennel provides more potassium, vitamin C and folate than celery and has much more fibre.
Parma ham is the best-known and one of the most expensive types of Italian salted, air-dried prosciutto. Cooked pancetta (salt-cured bacon) or coppa (salted, spiced dry-cured ham) may also be used in this recipe.