Heat butter and olive oil in a large pot over medium heat.
Add onion, celery, and garlic and sauté 4–5 minutes until softened.
Stir in flour and cook 1–2 minutes to form a roux.
Add tomato paste and cook 1 minute.
Slowly whisk in broth and white wine, stirring to prevent lumps.
Simmer 8–10 minutes until slightly thickened.
Stir in heavy cream, paprika, cayenne, salt, and pepper.
Add shrimp and crab and simmer 3–5 minutes until heated through.
Blend partially for smoother texture if desired.
Garnish with parsley and serve warm.