Psst! The savory secret to this recipe is the shrimp stock you are creating. *You can short cut the recipe and purchase cooked shrimp and fish stock, however the results are just not as mouth watering!
My husband is a huge fan of my gumbo - it was his brainiac idea to combine the burger and gumbo twosome. Hence, this recipe was born.
Pour the cup of water into medium size saucepan. Stir in salt,vinegar and one and a half teaspoons of old bay seasoning, bring to boil over medium heat.Add raw shrimp to water.Shrimp will turn pink and begin to curl in less then 2 minutes.Keep your eyes on the pot. Using slotted spoon remove several shrimp at a time as each begin to curl and turn pink.Place drained shrimp on a plate and toss with a teaspoon of old bay seasoning while shrimp are still hot.Put shrimp in a single later to cool.Let cool for 10 minutes then begin peeling shrimp,reserving the shrimp shells in a separate bowl. Devein and remove tails of shrimp, cut each shrimp into ¼ inch pieces and set aside.Place shrimp shells back into the saucepan of left over shrimp water.Add enough additional water to just cover the shells.Turn heat to medium, let simmer 15 minutes.Using a fine strainer pour shrimp stock into a heat proof bowl and throw away the cooked shells. Let cool.
Add butter to skillet and melt over medium heat until it just begins to bubble. Toss in sliced onions, coat well with butter cook for 20-25 minutes over medium/ low heat. Stir occasionally until onions have caramelized. Remove from heat
Pre heat grill to 500. Spray top of grill surface with non stick spray.
Divide the beef into 4 equal portions adding a teaspoon of shrimp stock into the beef, along with equally divided portions of sausage and shrimp to each patty. Form each portion into a ¾ inch burger. Try not to compact the meat tightly, but firm enough to hold the shrimp and sausage together in a patty. Brush each patty with the shrimp broth. Sit the burger patties in the refrig. while you make the gumbo mayo.
For the Gumbo Mayo: Whisk together mustard, mayo, 8 tsp. of shrimp stock and 2 tsp. of old bay seasoning.
Grill the burgers until golden brown and slightly charred on bottom side, about 2 and ahalf minutes for medium rare. Flip burgers and cook an additional 2 ½ to 3 minutes. Remove from grill, let burgers rest 3-5 minutes, meanwhile toast burger buns on grill sliced side down for a few seconds until toasted and warm. Remove buns and spread gumbo mayo on both insides of each roll, place burger on bottom roll then top with a romaine leaf and sliced tomato. Enjoy-Happy eating!