A Bite of Britain: Cockle Chowder in Bread Bowls

Name: A Bite of Britain: Cockle Chowder in Bread Bowls
Ingredients: 3 sticks celery; 1 onion; 3 cloves garlic; ½kg / 1 lb new potatoes; 2 rashers streaky bacon (optional); 500ml / 2 cups stock (fish, vegetable or chicken); 100g / ¾ cup butter; 75g / ¾ cup plain flour; 600ml / 2½ cups single cream (half and half); 100ml / ½ cup semi-skimmed milk; 100ml / ½ cup dry white wine; 300g / 10oz shelled cockles (or 3 standard jars, drained); 2 tsp salt; ½ tsp pepper; 1 round, crusty bread roll per person; Handful of parsley, chopped, to garnish