Rinse the pearl barley under cold water.

Heat oil or duck fat in a large pot or Dutch oven over medium heat.

Add the chopped onion and carrot and cook until softened, about 5-7 minutes.

If using celery, add it now and cook for another 3-5 minutes.

Add the diced duck meat and cook for a few minutes until slightly browned.

Pour in the water or broth. Add the rinsed barley and bay leaf.

Bring the soup to a boil, then reduce heat, cover, and simmer for about 40-50 minutes, or until the barley is tender.

Add the diced potato and continue simmering for another 15-20 minutes, or until the potato is tender.

Remove the bay leaf. Season the soup generously with salt and pepper to taste.

Serve hot, garnished with fresh herbs if desired.