Step 1

In a large stock pot over medium heat, heat oil. Add shrimp heads and shells and cook, stirring occasionally, for about 7 to 10 minutes or until color changes to pink.

Step 2

Add onions, carrots, celery, garlic, bay leaves, peppercorns, and water.

Step 3

Bring to a boil, skimming any scum or foam that floats on top.

Step 4

Lower heat and simmer, uncovered, for about 20 to 25 minutes, or until the liquid has turned to light-orange color. Occasionally skim foam on the surface and press the shrimp heads with the back of the spoon to extract more flavor.

Step 5

Using a fine-mesh sieve lined with a cheesecloth or clean tea towel, strain stock and discard shrimps and aromatics.

Step 6

Allow to cool and transfer to a container with a tight-fitting lid. Refrigerate for a few hours and skim off any layer of fat that rises to the top.

Step 7

Refrigerate for up to 3 days or freeze for up to 2 months.