Norwegian Fish Stock - cooking recipe

Ingredients

1/4 cup parsnip, coarsely chopped (no need to peel)
1/2 cup carrot, coarsely chopped (no need to peel)
1 large yellow onion, peeled and coarsely chopped (3/4 cup)
1 large potato, coarsely chopped (no need to peel-just wash)
1 teaspoon salt
6 whole black peppercorns
1 tablespoon parsley stems, chopped
1 bay leaf
3 celery ribs, with leaves-chopped
2 lbs fish (trimmings-heads, bones etc.)
4 quarts cold water

Preparation

Combine all ingredients in a 6 quart stock pot. Bring to a boil, partially cover the pot, turn the heat to medium-low and simmer for 30 to 40 minutes.
Strain the stock through a fine sieve into a large bowl, pressing down hard on the vegetables and fish trimmings with the back of a spoon to extract their juices. Diiscard solids.
Wash the pot and return the strained stock to it. Reduce the stock to about 6 cups by boiling it rapidly, uncovered, for about 20 minutes.
Restrain through a fine sieve or through a double thickness of cheesecloth lining a regular sieve.
Use for soup or freeze for future use.