Cook the beans in a pan of boiling salted water for about five minutes (you want them to bend a little - that is when they are most flavoursome). Drain the beans and add them quickly back to the hot pan, scatter over the ham and cheese, trickle over the olive oil and season well with freshly ground black pepper. Toss gently over a low heat so that the cheese melts to makes a warm voluptuous dressing for the beans. Serve immediately with crusty sourdough bread. Brie or camembert work well if you can't find taleggio.