1 1/2 pounds small (51-60 per pound) shrimp, peeled & deveined (shells & tails reserved)
1 cup clam juice
1/2 cup + 1 tablespoon vegetable oil, divided
1/2 cup all-purpose flour
2 medium onions, finely chopped
1 medium red bell pepper, finely chopped
1 rib celery, finely chopped
12 oz frozen sliced okra (sliced about 1/2 inch thick)
6 garlic cloves, minced
1 tablespoon fresh thyme, chopped
1/4 teaspoon cayenne pepper
2 bay leaves
1 pound andouille sausage, sliced 1/4 inch thick
1/2 cup chopped parsley
kosher salt & freshly ground black pepper, to taste
4 cups steamed brown rice, hot
4 scallions, thinly sliced
In a medium sauce pot, combine reserved shrimp shells and tails with 1 quart water, and place over medium-high heat. Bring to a boil, then reduce the heat to medium-low to maintain a simmer for 20 minutes. Remove from the heat and strain. Discard the shells and tails. Combine the shrimp stock with the clam juice and 1 quart cold water. Set aside.
Add 1/2 cup vegetable oil to a large Dutch oven or sauce pan, and heat on medium-high for about 2 minutes. Reduce heat to medium, and stir in the flour with a wooden spoon, stirring constantly to work out any lumps. Continue stirring constantly, until the mixture turns a deep shade of brown (a mix between the colors of milk and dark chocolate) and gives off a toasty aroma, about 20 minutes. Add the onion, pepper, celery, okra, garlic, thyme, cayenne, a good pinch of salt and a few good grinds of pepper. Cook on medium, stirring occasionally, until vegetables are tender, about 10-15 minutes.
Slowly add half of the stock mixture and stir vigorously to combine. Add the rest of the shrimp stock mixture. Bring to a simmer. Decrease heat to medium-low and simmer, uncovered for 30 minutes. (You may need to skim the surface from time to time, to remove any scum that collects on top.)
As the soup simmers, heat a large sauté pan over medium-high heat for two minutes. Add 1 tablespoon oil to the pan and heat one minute more. Add sliced andouille sausage to the pan in an even single layer and sauté until crisp and golden brown on the bottoms, about three minutes. Flip over the slices and sauté the other sides, about two more minutes. Remove from the pan and set aside. (If you have too much sausage to fit in a single layer in the sauté pan, do this in two steps.) Once all the sausage is sautéed, add a quarter cup water to the empty sauté pan and bring to a simmer, scraping up any bits and pieces sticking to the bottom of the pan. Simmer about two minutes, then pour these juices into the simmering soup.
After the soup has simmered thirty minutes, stir in the sautéed sausage. Simmer thirty more minutes. Stir in the shrimp, then simmer until cooked through, about five more minutes. Turn off the heat, and stir in the parsley. Season to taste with salt and pepper.
Fill serving bowls with a generous ladleful of gumbo. Top with about a third a cup of hot steamed brown rice. Garnish with sliced scallions.