Step 1
Melt 6 tablespoons butter in a large pot over medium heat. Add onions, garlic, and salt; cook and stir until onions soften, about 5 minutes. Add lobster shells, mushrooms, apple, red bell pepper, carrots, and tomato paste. Cook and stir until vegetables soften, about 7 minutes. Add water, paprika, curry, tarragon, chili powder, and cayenne pepper. Simmer soup over medium-low heat, uncovered, stirring occasionally, about 2 hours.