Make sure that your ingredients, utensils, and pots are laid out and convenient before turning on the stove. This recipe moves quickly and relies on constant whisking so having everything laid out will help keep you from scorching the roux.
In a small bowl, combine the salt, cayenne, pepper, basil, and thyme. Set aside.
Bring 2 cups of the seafood stock to a boil. Turn down heat but keep hot. Cook the rice as directed.
In a large skillet, heat the oil over high heat until it begins to smoke (looks like slight steam), about 4-5 minutes. Gradually whisk in the flour until smooth. Continue whisking constantly until the flour is a red brown color, about the color of a new penny, 3-5 minutes. Immediately remove from heat (don't just turn of the burner).
Add the celery, onions, and bell pepper. Add ½ (about 1 Tbsp) of the seasoning mixture and stir until well combined.
Over low heat, gradually add the pre-heated seafood stock into the roux, and whisk until combined. Continue whisking constantly and cooking a few minutes until flour taste is gone.
In a large saucepan or pot over medium heat, melt the butter. Stir in shrimp and saute until just pink on both sides.
To the shrimp, add the remaining seafood stock, the roux mixture, and the remaining seasoning mix. Stir until well combined and hot, about 4-6 minutes.
Serve in bowls with a ½ cup of rice in the center. Sprinkle green onions over top.