Sprinkle the shrimp with Creole seasoning and salt. Toss the shrimp to coat completely. Reserve.
Heat 1 tablespoon of oil in a large skillet over medium-high heat. When the oil is hot, add the seasoned shrimp and saute for 2 minutes. Turn the shrimp and cook for another 2 minutes. Remove the skillet from the heat.
For the dressing: Heat another skillet over medium heat. Add the remaining olive oil and andouille sausage and let render for 3 minutes. Add the shallot and garlic and saute for 3 minutes. Add the parsley, salt and pepper to taste. Deglaze with balsamic vinegar.
To serve: Place the salad greens on a platter and top with seared shrimp. Dress the salad with the andouille mixture and croutons. Serve the dish immediately.
For the croutons:
Preheat the oven to 300 degrees F.
Combine the diced bread, olive oil, Creole seasoning, salt, and pepper in a large mixing bowl, and toss quickly to coat the croutons well. Transfer the croutons to a baking sheet and spread them out in a single layer. Bake, rotating the baking sheet front to back midway through, or until the bread cubes are crisp all the way through and golden, 25 to 30 minutes. Remove the bread from the oven and set aside to cool completely. Store the croutons in an airtight container at room temperature.
For the Essence:
Combine all ingredients thoroughly.
Recipe from "New New Orleans Cooking", by Emeril Lagasse and Jessie Tirsch, published by William Morrow, 1993.