1. Peel the shrimp and place the shells in a saucepan with the water, lemon zest, parsley sprigs, 2 garlic cloves, peppercorns and celery leaves.
2. Bring the mixture to a boil, reduce heat, and simmer 45 minutes.
3. Strain and measure out 1 cup of the liquid.
4. Heat the oil in a large heavy-bottomed frying pan and add the onion and 4 garlic cloves.
5. Saute over medium-low heat until the onion is tender and beginning to color and add the cumin, cayenne, salt and pepper to taste and shrimp.
6. Stir together for a minute or so and pour in the cup of liquid from the shells.
7. Bring to a rapid boil, then reduce heat to a simmer and cool 10 minutes.
8. Transfer to a serving dish, sprinkle with the cilantro or parsley and serve hot or allow to cool, with rice either underneath or on the side and lemon wedges for garnish.

Makes: 4 to 6 servings