Green bean minestrone

Name: Green bean minestrone
Ingredients: 1 onion, finely chopped; 1 garlic clove, finely chopped; 1 carrot, finely chopped; 1 celery stick, finely chopped; 2 tbsp olive oil; 70g pack cubetti di pancetta (optional); 1 bay leaf; 1 ½l vegetable or chicken stock; 100g small pasta shapes, such as stelline or orzo; 300g mixed runner, green and podded broad beans; 100g/4oz spring cabbage, shredded; 4 tbsp pesto; crusty bread, to serve