Mackerel Stew

Ingredients

• 4 large mackerel fish, cut into 2-inch slices
• 1 leek, sliced
• 4 carrots, peeled and quartered
• 1/2 celery root, thinly sliced
• 2 tablespoons butter
• 1 1/2 cups vegetable stock
• 1 1/2 teaspoons salt
• 1/2 teaspoon freshly gournd black pepper
• 2 tablespoons chopped parsley
• parsley, chopped, for garnish