Place heads and shells in large pot, add water, quartered onion, bay leaves and 1 T. salt. Bring to boil, reduce heat and simmer, uncovered for 30 minutes or more. Remove from heat and strain. Discard peelings and set stock aside.
In large cast iron pot, combine oil and flour and make a roux of peanut butter color-approximately 15-20 minutes.
Add chopped onion mix to roux. Stirring and cook until tender, about 6-8 minutes.
Add stock and whisk to blend into roux.
Bring to boil, reduce heat and simmer for 1 ½ hours.
Add seasoned shrimp to water. If using gumbo crabs, also add at this time.
Simmer 20 minutes. Add crabmeat if you want at this time.
Season to taste with salt, red pepper and garlic powder.
Remove from heat, add parsley and green onions. Serve over hot rice and garnish with chopped boiled egg.
Notes
*****I like to add gumbo crabs and crabmeat to make a crab/shrimp stew. Crawfish can be substituted for shrimp
Recipe by Geaux Ask Alice! at https://geauxaskalice.com/shrimp-stew/