Melt the butter in a pot over medium-high heat. Add the green onions, garlic, sweet basil, salt, and cayenne pepper. Cook for 30 seconds, stirring constantly.
Add the crawfish tails and cook for 2 minutes, stirring occasionally.
Add the 2 cans of Blue Runner® Creole Tomato Basil Bisque and the cream. Bring the mixture to a boil. Reduce heat to low. Add the Parmesan cheese and stir until well blended. Simmer for 5 minutes. Serve.